Best $500 System?

I like the powered monitors and CD with variable output. KISS it. Active Quad 11l/12l (best as nearfield, but great all-round), Tannoy Revolution, etc.

I'm impressed with the JBL 4208 (and 4206) as an inexpensive pair of used speakers (not active) if you buy an amp. For a sweet top end, try some older Mission speakers. Heck, $100-200 can buy a lot of speaker for the money. I have a high end system, but finding the best "bang for the buck" is always a blast.

There are a pair of Epos 3s that came up today. Can be had for $180 including shipping. Pair them with a used integrated. Otherwise, a Pioneer A20 can be had new for $270.

The amplified speaker route is also viable. Get a pair that has the volume and amp in one of the speakers which drives both speakers.
Some have a built in DAC so that disc player can be run in via digital out. 

I suggest the audioengine HD3. They are amplified, veneered, and small. Perfect for a woman not concerned about bass. The JBL 305s sound great for the money, but I don't think many women would accept their looks. The Vanatoo Transparent one is my other suggestion. Superior sounding to the HD3, but $100 more in cost.

I'd go with a NuForce DDA-120, an integrated amp with a nice DAC. It is an Absolute Sound Editors Choice at $499. Currently on sale at Audio Advisor for $299. Available in black or white. It comes equipped with a Bluetooth dongle. 
If your friend has a DVD or CD player with a digital coax out, buy a cable & hook it into the NuForce 's digital input.You avoid the cheap internal DAC in the player and now have a CD transport connected to a very capable DAC & great amp. If she doesn't have a player or it doesn't have a digital out, (optical or coax - the NuForce handles both), then  buy a DVD player with a digital coax or optical out. Best Buy, Target, and other discounters have a variety for $35-50. I'd stick with a major brand, like Sony, Samsung, Phillips, or LG. The DVD players work, but are usually slower to cue up than a CD player. On the speaker front I'd go with Pioneer SP-BS22-LRs. Best Buy usually has them at list $129 pair, but periodically takes them down to $100.  I'd try Audio Video Logic on line, they have them on special at $99 a pair. Not sure if they would ship them for free, but they are excellent retailers/enthusiasts -so talk to them. Usually Best Buy will match a bonafide authorized retailers online price, but if it is a wash give the specialty store your business and start a relationship. I've owned the Pioneers (as well as the other Andrew Jones darlings the ELAC- B5, B6 & UB 5) I think the NuForce amp and Pioneer speakers would have great synergy. Should be a nice system for CDs and Bluetooth streaming.