Big genealogy buff here.
Ancestry.com is well worth the fee and is absolutely the best out there as far as the sheer volume of databases and information. I have been a member off and on for years, as my time allows to research. Right now is an off period. I would suggest to set aside a block of time and research like crazy and then close the membership when you don't use it so much.
However - Most main branches of libraries have a history room, and you can access Ancestry for free with your library card.
Also, most libraries have access to HeritageQuest Online and with your library card barcode you can access that database from home for free.
familysearch.org is free
All the USGenWeb sites are free.
All the forum (Ancestry, rootsweb, genealogy.com) boards are free and have a ton of info out there.
Cindi's List and Linkpendium are great too.
Findagrave is wonderful!! I have had many a break through because of the wonderful volunteers on that site.
And as other posters have mentioned - Google is your friend.
Get your tree online (properly sourced!!! of course) as soon as possible, so people can find you. I love all the genealogy emails I get, and love to exchange info and photos.
Just remember to source everything - that way other researchers or family members can come behind you. And most important - Don't believe anything you see on the internet unless there are sources attached to it.