I have always struggled with memorizing jazz standards, as I've spent years playing other types of music rather than jazz gigs. So, I kind of envy the bassists who know all the jazz standards, and I've decided to spend more time learning them thoroughly, and working through them in different keys. I found this site: Jazz Standard Repertoire, which I highly recommend. It's obviously a labor of love for David Miller, the chap who created it. (I say chap cuz he's based in London). I plan to use it in the coming months to master more tunes. I invite you to have a look at it if you arent' familiar with it. This and IRealBook are great learning tools, I think.