I was fortunate enough to have a friend at work who has a large assortment of pistols that I got to shoot my first time out. Desert Eagle .45, 4" Kimber 1911, Glock G26, G26 with .22lr conversion, CZ 2075 Rami .40, some little cheapie European .25ACP with a goofy magazine release(no button, you yank the magazine out... ha), and a Springfield XDM 9mm...
Having all of those different guns/calibers to shoot my first time out was really nice in finding how much the overall weights of guns affected the perceived recoil, and the way different calibers felt in relation to each other.
It is my personal goal to eventually have 4-6 pistols in different platforms/calibers strictly for having a variety of things to shoot for fun/friends/introducing new people to shooting. I'm going to be picking up a .22lr MK3 next week to save money myself, but I suspect it will be a great starter gun when I take someone to the range... after that a 9mm will bridge the gap between it and my .45.