http://www.virtualsheetmusic.com/
is “Classical Sheet Music Downloads®
High Quality and Exclusive sheet music to download and print instantly”. I purchased 1 year membership and I’m satisfied. Scores are nice but there is no fingering.
There are other sites too, one offered lots of choral music unlike this one but i forgot their name. I chosed this one becouse it offers Brahms’s Hungarian Dances transcript for piano for four hands.
Please if you know other sites with music sheets let me know.

It was great experience. They rock! oh man how they rock…

http://www.nospank.net/fyog.htm

This is crucial book to read!

According to this review , Lehrmann’s book would be better choice.
Listmania great list of resources
” I can also recommend the amazingly well done articles on comparative linguistics and on the Indo-European family in the Encyclopedia Britannica .” link

Well i must admit that i wanted a Indo-European languages intro, not IE language.
Baldi’s book – can’t be used as a primary source
Firtsin good, undergrad level

A must-read!