I'm a Ruger "snob" so i'm going to recommend the SR9c. Its the perfect carry gun, has the 10 and 17 rd mags, and has a great trigger on it. When you have the 17rd mag you can tell the barrel is a little too short but I love takin mine out. Theres one in the classifieds right now for $425 with a holster and lots of upgrades I believe. Might be able to get him down to your price point.
I own M&Ps (Compact and full size) and a CW-9. The CW9 is a great concealed carry weapon - clean lines, very slim, small frame BUT it is not, IMHO, a great heavy duty range work weapon. I concur with an earlier comment - if you really want to shoot a whole lot then get yourself a good service-type weapon. M&Ps and Glocks both come to mind - new or used - just find the best cost-benefit balance you can. Since you wanted recommendations...I prefer the M&Ps series but truthfully either will serve very well. I happen to like the Made in USA idea but that is just me (its also why I only buy New Balance "Made in USA" running shoes)
If you are retired or active duty military or law enforcement - you can get great deals on service weapons from Buds Police Supply and the M&Ps come with a $50.00 military and police rebate too! I think Glock may also offer a military rebate.
New: Sig Pro 2022 ($399 at Buds), S&W SD-9 ($378 Buds)
Used: CZ-75B, CZ P-01, Glock 17 or 19, S&W M&P, Springfield XD or XDM, Walther P99 and Ruger SR-9.
If you bump your budget to $500, you can get many of these guns new.
I would reccommend either the sprinfield xd(not the xdm) or the smith and wesson m&p 9. The s&w has the different backstraps that allow you to make them fit your hand better and it is a quality handgun. Here is a link to the best deal I have found on them. I called them last week and they have them in stock and to have them shipped to your local ffl is $25 extra. Plus if you are military, verteran or LEO you can get an additional $50 rebate from s&w. So a new m&p 9mm for $350ish...great deal.
Might I suggest the S&W 3rd Generation 59XX series.
CDNN has a bunch in for sale, 299.99. http://www.cdnninvestments.com/
Download their catalog an look on page 29.