Abandoned Arts has a number of books for under a buck. The great thing is that for the price of a 24ox bottle of Mt. Dew (in some places) you can have a some crunch. Since they are grouped by theme and use you can usually get exactly what you are looking for.
Feats of Seduction is one of those products that you already know if you want or not. I will contend that there is enough here to for ANY class to use and gain benefit of outside of seduction. I few I read and though they would be great for an illusionist or a cleric as well as a bard or a rogue. I would also say that if you are playing in predominantly urban environments then there is a lot here you can use.
As will all of the AA books this one has a cover page and an OGL page. The rest is dedicated to the 10 feats. Nothing crazy here, these can be added to any game without worry.