I haven't looked for Access 2003, but for Access 1, 2, 95, 97, 2000, and 2002 every serious developer needed the Litwin/Getz 2 volume set (the early ones were 1 volume), Access Develop's Handbook by Sybex. It isn't as tutorial as many other books, but once you get past the tutorial stage it is a necessary reference book. Don't leave home without it. Those guys are the best.
Lyrics, I found myself in a similar situation about 6 months ago, and I picked up these two books and pretty much read them cover to cover, and I refer to them both almost daily. They complement each other nicely, but if I had to choose one, I'd go with the first.
Those books and this website have brought me up to speed quite rapidly. Obviously you won't be a Microsoft MVP in 6 months, but you will at least gain the experience to know the right questions to ask, which is always key.