I've never shot nudes unless it was with a current girlfriend. It's so much easier to take intimate photos of a girl you're actually intimate with. I just wish I had taken better photographs of girlfriends past. Of the gigabytes of images I took of my last GF, they're nowhere near the caliber of images I'm planning for my next model.
It's good to know Model Mayhem actually works for some--thanks for posting that report. Many of the models there seem like "pros," appearing to be trolling mainly for amateur photographers' wallets. Glad to know that's not (always) the case. It's also good to know about the MeetUp site, too. Many of the "group photographer" meetings charge a fee, but do provide shooting space and lighting equipment. Some of the models, however, aren't always the most model-looking. I haven't tried either of these sites myself--this is just what I gleaned from a quick scan of the websites.
Walking up to girls you meet in everyday life seems to work pretty well. Getting them to show up is always the issue. I've used online casting sites for short films, and that's worked out fairly well, and everyone I booked actually showed up. But trying to get really beautiful women to show up for your still shoot is always a challenge. The trick is to find someone beautiful enough, yet still green enough that they haven't yet made any pro photographer friends (i.e., they still need you).
A couple of tips, learned from experience:
1. During your initial discussions with a model-candidate, try to shoot a couple test shots right then and there. A lot of women are stunning in person, but just don't photograph that well. Some women are very pretty, but don't have an angular-enough bone structure in their face for close-up portrait work.
2. Also, try to take at least one full-body shot. Again, many women who look perfect in real life (and, who actually are), can still look a bit out of proportion for glamour or fashion photography. The most photogenic people are always a bit skinnier in real life than most would prefer. That's why real fashion models are so thin and tall.
3. Make-up, hair, and manicures: make-up is extremely important in glamour or fashion photography, and can sometimes take hours to apply. Try to get a student, and offer them a "kit fee" as compensation (about $50). Hair is another big issue. Some stylists will offer their services for prints--check local salons. Shooters on a budget usually try to get one person to do both hair and make-up. Hands: if the model's hands will be featured in a shot, I always offer to pay for a manicure. This way I can specify the type and color (a French manicure is always a safe bet).
4. Wardrobe: if your model has enough fashion sense of her own, then she can style her own shoot. While professional stylists are typically beyond the reach of most amateur photographers, you can always try to make a trade-out deal with a local merchant or designer. Or, you can also shop your local outlets, keep the tags on everything, and return everything at the end of the shoot. For shoes, be sure to tape the bottoms, or else they'll be unreturnable.
I work with several professional stylists. Yes, we've talked about shooting--they get the models and the clothes, and I give them the files. But it's always time and money. No one has time because they're all busy making money instead of trying to produce art. We talk, but nothing ever materializes.