A lot of the videos posted, particularly faliaphotography, are good sources of ideas/info generally. Addressing your specific questions from my experience (I'm aware that this is all merely my opinion and that there are likely exceptions to everything I say below):
Wife got her CCW recently and picked up an SR9c to match... we've been trying to figure out a good carry method for her though.
Depending on her body size, that may be a big gun for her to start CCW with. I'm all for carrying a serious caliber with significant capacity, but if she's remotely slim & stylish, and it sounds like she is, then that gun is going to be a serious challenge for on body carry as a starting point. Having gone through this and watched a number of women do it, I recommend starting with something smaller, even what most here would deride as mouse guns - it's going to be much easier for her to CCW something the size of an LCP - there are less compromises for her style and comfort. If she succeeds in carrying that, she can always move up to the SR9c later, but if CCW becomes frustrating and negative at the beginning, it can quickly become a chore and something that will not be a regular habit.
I picked her up a cheapo Fobus just for range/OC purposes... but with most of her tops being "fitted" it looks asinine trying to conceal it. Overpriced and in her opinion hideous purses with built in holsters are a no-go, as would be a fanny pack. (I took the girl out of the city, you know the rest)
I agree with her on the purses. I know someone already recommended Gun Tote'n Mamas...this is completely an area of personal preference and style, but I have yet to find a holster purse company that makes things I would remotely consider carrying from an aesthetics point.
This doesn't rule out purse carry - unless she needs some special feature like a lockable compartment, have her look for purses she likes that have a stiff construction (i.e. something other than a hobo bag, preferably something that can "stand up" on its own) and a pocket or compartment of the appropriate size. Then get a pocket holster to fit the gun. Works just fine. If she wants it even more secure, she can sew the holster into the purse.
If she's seriously into her purses, you may want to consider having a holster purse custom made. This is NOT cheap, but if she appreciates quality leather goods and can limit herself to not needing a different purse for every day of the week, it can be an attractive and functional option. A lot of the holster makers do some stunning work.
Any other thoughts? I'm not sure an IWB on her would look much better and with women not wearing undershirts often I doubt it would be comfortable.
I have never found IWB to be problematic without an undershirt. Her mileage may vary of course, but don't discount this option. Whether IWB will work is more dependent on 1) her body type and 2) what compromises she is willing to make with her wardrobe. You cannot wear baby doll tees and skinny jeans and CCW on body. There has to be SOMEWHERE to hide the gun. She can pick where, but she may very well need to change her style in order to CCW. It sucks. More than most guys appreciate.
She may need several options for different styles of dress.
Appendix carry seems to work well for a large number of women. Unless she's an A cup, she can find plenty of shirts that will showcase her assets and leave enough room to conceal a small pistol at the appendix position. Anything past 2:00 is GENERALLY harder for women IME. Have her try the holster at all possible positions. Remember that dark colors and patterns will mask the gun much better than light colors and plain fabrics.
If she wants to try thigh carry, do NOT skimp on the holster. I agree with falia's recommendation on thigh holsters...there should be a recent review in this section of the forum. Works great, but not likely to make her happy with something as large as a SR9c...I have mine set up for a slim .380 and it's still only compatible with flared skirts. There's no way I could conceal or be comfortable with anything larger, but that will of course vary with body type.
Don't automatically rule out ankle carry - I hate it personally, but I've seen it work great for a few women and as long as she wears flared pants, she can keep the tight shirts and snug low riders.