I would highly recommend a vintage Stanley No. 4. They are very common and also quite inexpensive. A very nice quality plane can be purchased for less than $50. You may be tempted by the new planes but I've found the quality of older planes to be superior to modern planes under $100. If price is not a concern, I would also recommend Lie Nielsen and Veritas (Lee Valley) planes. These are both modern makers of planes that believe in producing quality planes. Despite the low price tags of some other planes I would not recommend most of them. As always, you get what you pay for.