Welcome to the Tekkit Wiki, if you do not know what Tekkit is then you can get it here. Yes, you do need a Minecraft account to play online just as any other version of Minecraft.
http://technicpack.net/cgi-sys/defaultwebpage.cgi
^at the moment, their website is down. if you do not have Tekkit and or the Technic pack then I can give it to you!

This wiki includes every block and every craftable item in the Tekkit mod.
To find a specific block, search for it in the search bar to your left.

If you are seeing this page, sorry but I am not done yet! :P