Jeff, I feel your pain, although I've not had a question list quite lke that one. You're right though, you do feel guilty when the recommended solution is "buy my book". If the solution is too complex to get over in a simple email I tend to try and give some pointers, list a few sites wth help and solutions and recommend the book. Dumping a complete solution on someone may well be what they want, but it isn't often what they need and they don't learn as much. It's a tough call though.