You might find this page at the
NCSE, and it's links a useful resource.
I'd also recommend getting a recent textbook - preferably degree-level, not the High School texts Wells focusses on (a very odd choice if he wanted to seriously deal with the evidence for evolution).
I found Mark Ridley's
Evolution to be quite good, although I'm neither expert enough nor familiar enough with the competition for my opinion to carry much weight - although the fact that I found it to be accessible despite having little formal eduication in biology must count as a point in its favour (I have the 2nd edition, but the 3rd has some significant new material and probably should be preferred). Mayr's
What Evolution Is is cheaper but less detailed (because it's much shorter) and not the best choice for dealing with the issues Wells raises as a result.