Twitter has two different search resources - Basic search which you can get to from the home page, and Advanced search, which you can't. I've written about these on my website, and you might want to take a peek at my Twitter search engine page.
In the course of exploring I have found some alternative search engines that you might want to take a look at.
AskTwitr looks very simple, with a Google like interface. Search results however are displayed in a rather different fashion. The top of the results screen gives a world map, with recent tweets popping up and disappearing. Below are image and video results from Flickr and YouTube, with text tweets below those. Nice and simple, with an attractive style.
Backtweets is simple in design and concept. Type in a URL and see the results, which are simply tweets that mention said URL. What is particularly nice about this resource however is that it takes into account URL shortening services, so you can find links even if you don't know how they've been shortened. Cracking idea!
Cloud.li is a little odd, and I'm not entirely sure what to make of it. The interface is simple 'search' and 'exclude' and you type in as appropriate. That then results in a tag cloud (presented on a size basis) with other terms, which link you directly into an advanced search over at Twitter. Good if you're not sure of what you want to find I suppose, and need some keyword ideas to help.
Flaptor is a fairly straightforward engine, listing results, but it does also offer a trending stream for the search term over the last month. Does have some useful other trending options over time periods, what's hot at the moment and so on, but this engine doesn't personally offer much to excite me.
Now Icerocket is one of my favourites, so I'm slightly biased. It has a Twitter tab, provides results in a tight compact format, provides an RSS feed to go with them and also has a 'Big Buzz' option, drawing in Twitter results, blog postings, Friendfeed, video results, news and images for a comprehensive 'what's happening this second' approach that Big G can only dream of!
Monitter lets you monitor (groan!) up to three keywords in real time, in 3 different columns. This leads to a fast moving set of results (depending on your terms) and you can limit to tweets within a specific location. It's not really a search engine as such, but to be fair, it's not trying to attempt that.
MicroPlaza is another engine that takes results from Twitter, finds associated weblog postings, and matches the weblog posting to individual tweets. It's a clever idea, and is a nice twist on the search idea. Took me a while to understand what was happening on the screen, but once you realise it, well - it's obvious! There's also an RSS option as well.
Musebin is supposed to be some sort of search engine that finds references to music on Twitter. It lists tweets that match your musical interests, but in all honesty I didn't really find much in it that was original, though I admit I could be missing something!
Nearby Tweets is an engine that Twitter could learn from - it really does the geographic thing well - far superior to the Twitter offering. Locations are listed clearly and concisely so that you know that you're searching the right locale, though I would like to see alternatives being offered. The engine offers a list of Twitterers nearby as well as tweets. Nice, simple and clear. Very easy to use.
Tweetmeme displays and tracks the most popular links on twitter every 5 minutes, based on the number of tweets. Kind of a glorified trending resource, rather than a search engine. It also offers links to blogs, images, video and audio.
Tweepsearch will search the biographies of all of your followers or you can do a keyword search of all the biographies on Twitter. Great if you want to find all the librarians on Twitter for example. You can then further limit a search to one of the people you've found, and you can also do location based searching as well.
Tweetscan searches for tweets based on your keywords and by individual if required. It then displays an update every couple of minutes. So more of a live search trending tool I think.
Twendz is a Twitter mining Web application that utilizes the power of Twitter Search, highlighting conversation themes and sentiment of the tweets that talk about topics you are interested in. It provides a word cloud around a topic as well. Another of the trending tools really.
Twibs is a business based Twitter search engine, listing 6,313 business, 190+ that are running promotions. Results provide avatar, biography, followers, location. RSS feed as an option.
TweetGrid acts as your own Twitter dashboard. It allows you to search for up to 9 different topics, events, converstations, hashtags, phrases, people, groups, etc in real-time. As new tweets are created, they are automatically updated in the grid.
Twithority is supposed to find tweets for you and display them in an authority ranking system. Quite how it arrives at what/who is 'authoritative' is not clear. I think it's based on the number of followers, which isn't overly impressive as a method of working out authority.
Twitscoop is a straightforward real time search, with a tag cloud that's changing size by the moment. Visually looks quite fun, but I can't really see it as being much more use than any of the others.
Twitterfall is a resource that I like, even if it doesn't have a fancy logo. It's is a way of viewing the latest 'tweets' of upcoming trends and custom searches. Updates fall from the top of the page in near-realtime. Really nice to use this as a background at a conference for example. Far superior to some of the other search/trending tools, I could see myself using this one on a regular basis, particularly to keep up to date with an event.
Twopular is another trending tool. It provides links to trends right now, last 2 hours, 8 hours, day, week or month. There is a search option, well hidden. It's also rubbish. I tried a search, up popped a list of suggestions and because the term I was looking wasn't there it just chose one itself, which happened to be a not particularly nice NSFW phrase. Thanks, but I won't be coming back to this one again.
The #hashtags site limits searching to hashtags, so you really have to know what you're looking for before you start. Results provide the tweet, time and that's about it. I played with a few tags, but it didn't seem to update as often as I think it should do, so I'm doubtful as to its value.
So! There we have it. 20 alternatives to Twitter search. If you know of any that I've not listed, please let me know and I'll add them in via comments.