Ahhww I thought we had discussed the uke thing a while back on that other G&L enthusiast forum! Can't talk her into a mando?
'cause its you, I had a word to my uke playing mate Tony. Not sure what sort of price range you have in mind but he suggested that a uke in the $150 price range would be a good price point for reasonable quality starter instrument that won't frustrate a beginner with issues like high action or not staying in tune. You might get away for less than that tho given that you are in the USA rather than AUS. He suggested Kala as a reasonably safe buy. Oh, and he suggested that unless she has really small hands, a Tenor is probably the best size for a beginner.
As for books/DVDs he recommended anything by Jim Beloff. Other stuff he suggested were good quality strings (Aquila) and maybe a clip on tuner as ukes don't hold their tuning as well as guitars.
cheers, Robbie