Originally posted by pianojerome:
SheetMusicPlus is good. Amazon.com is also a very good source, but I'd go to SheetMusicPlus first.
The trouble with Amazon is, of course, its lack of a wide range of publishers. Just last night, I took advantage of the "used" retailers (I hardly ever buy the "new" items on amazon.com anymore, because the "market place" shops are mostly wonderful, and you can get some things for half price or less!--and they're in perfectly good, if not perfect, condition) and purchased 4 music books from Dover for less than the price of just three of the books new, as bought on Dover's website.
But there aren't very many other publishers on Amazon, if any (maybe one or two Kalmus editions and a Music Minus One or something), so if you need or want to go outside of Dover, then, yeah, sheetmusicplus.com is probably the best.
And for REALLY rare scores, this is an absolute must (because even SMP.com is limited in its list of composers, and sticks to *relatively* well-known pieces): http://www.overturemusic.com/overture_publishers.cfm
Also see the "search" function on the top bar. Put in the composer, find what you want, and it'll do all the shopping for you--that is, it finds the appropriate publisher (for instance, Musica Obscura) and a store for you. Nifty! The prices don't even seem half bad, either. At least not when compared to a recent discovery of mine at a local store, of EMB's Liszt editions, which seems to be a series comprising most of Liszt's work--some of them were up at a cool $60! I suppose it's worth it if you reaaaaally want those pieces. Some of them did look rather intriguing. Not something you hear at the retirement home every day, at least.