Wardrobe spinoff: Stain removal secrets

Spinning off of all the wardrobe posts, I don't dress up a ton, but I like to wear jeans or chinos and nice-ish t-shirts, shirts, sweaters, etc.  I usually shop at j. crew and banana republic, and while I don't spend a crazy amount, my clothes aren't exactly disposible either.  Stains are unavoidable and while I have learned to get out grease stains pretty well, I'm still struggling with other things.  I ruined a brand new pair of khakis the other day.  I sat in residue from one of DS's "slick sticks" and got red stuff all over my pants.  I threw everything I could think of at the stain and got most of it out, but ended up bleaching a big spot all around the stain (I did not use bleach, though). What should I have done?

So, this is a longwinded way of asking...what are your stain removal secrets?  Any online lists or charts?  Any stain remover sprays or gels or homemade concoctions?