Considering that he played Rooney against Bayern and has already bought a (young) striker, I think Fergie knows what he has to do. In the striker department, at least, I think he has more faith in Anderson and Carrick than is required to start fishing for a high-end replacement, especially when he's still got the experience of Scholes and Giggs and Gibson doesn't look too shabby. And make no mistake, if he's gonna bring in a midfielder, only high-end will do. There's no point in bringing in a young gun, or someone who still needs to prove himself right now.
If I were Fergie I'd look into getting Modric off Spurs, or (and I know this will sound ridiculous but) Benayoun from Liverpool. Not sure he (or Luka, actually) would be keen on a move, but he's experienced and not that old, and he's a good playmaker. Not exactly top stuff, any of them, but if you're strapped for cash, the rivlary with Pool could be offset by their financial woes, and he'd be cheaper than Modric, or any wordclass playmaker.
Cheers for the result today, btw.