Depends on the scale of the "skin and flesh" in question. Most folks would use Vallejo for figures, since they are very thin (almost transluscent) and if you're painting figures you want to build up the layers.
Check here:
http://www.ttfxmedia.com/vallejo/cgi-bin/_modelis.asp?p1=ing&p2=modelcolortecnicas
It's Vallejo's guide to painting figures with their Model Color line. It can be applied to just about any type of acrylic paint. Keep in mind that Vallejo paint is very thin (as stated above) so if you're using another brand, thin it out to get it somewhere between airbrush consistency and straight OOTB (out of the bottle).
Also depends on what figures you're doing and the climate they are in. For my Challenger I tank commander (think desert, with rolled up sleeves), I used a two parts XF-15 Flat Flesh to one part XF-64 Red Brown to get a tanned look. I thinned it out about 50/50 with some X-20A thinner and build up three or four coats. He looks OK, but was the first 1/35 figure I've done in 20 years. I guarantee you that the 1/35 Wehrmacht in winter gear won't be getting that treatment, but personally the XF-15 is waaay too pink looking for me. I'll probably try different mixes with XF-57 Buff and a couple other colors to see if I can find the right mix.
Just my and I'm by no means a figure guy. Hopefully Al or some of the figure gurus will help out more.