If there is a tool for doing something offline, there is often an internet-based equivalent that has added social functions. A list of such tools would be rather pointless - since such a list would be out of date pretty much as soon as it was published. However, there are a few hints to set you on the right path.
Go2Web2.0 contains a rather impressive collection of web 2.0 applications. According to the site: "We built this application to enable people to stay up to date with all the new & hot services that are born daily into the web. In many cases, Go2web20 has been the first to report the existence of a new application." Although it would be nice to have one place to go where everything you need is conveniently listed and categorised this does not happen; the internet is in a constant state of mandala-like flux.
There is one piece of advice I have found helpful. That is if you can't figure out how to use an application - at least the basic functions - in about a minute then simply move on and find another one. Because there are so many applications available, and many of them provide a free service that can be upgraded with a subscription - a model called freemium - there are plenty to choose from. A further tip is to use the "help" button. It is usually located at the top of the screen (and often in the right-hand corner). This will be able to provide you with a great amount of detail. Alternatively, there is the option of simply googling the information or posting a message in a forum. However, you should only ask questions in a forum once you have actually looked for the answer; RTFM is not a good response to receive!
Here are some tools I find useful.
Wikipedia. But of course. It is interesting how much this source polarises people. From those who claim it is one of the best things. Ever. However, some studies have shown that it is as accurate as Britannica. There are others, particularly academics, who feel that it should be avoided at all costs. This view partly comes from attempting to teach critical thinking skills - although it is debatable how simply banning something teaches students to be critical about sources - and partly because the information is not peer reviewed by others who have gone through many long years of knowledge acquisition. However, with anything you read online, you should read it critically. For more information, the University of Otago Library has a good, simple guide entitled "Why Not Wikipedia?". Incidentally, the page also has some great hints about using both Google and Google Scholar.
Blogger. The platform you are currently reading this blog on. I find it a useful tool because it links into my Google Account - so everything is under one username - but some other popular options are WordpPress or tumblr. I'm personally not a fan of tumblr - I find it too limiting and they used to lack a comment feature.
An RSS feed reader. It makes life so much easier when you don't have to go to different websites to get information; you can be much smarter and get the information to come to you. I use google reader, because it links into my account, however this article outlines the popularity of different types.
A social bookmarking tool. I like delicious because I started using it a while ago.It doesn't really matter which you use but having one is a good idea since it means you no longer need to worry about not having your bookmarks with you wherever you go.
In short: there are many tools you can use. Once you find one share the love and tell others what you think of it. Have teh funz!