Just make sure it's a "burr" type grinder rather than a "blade" type. The burr grinders are more expensive but are better quality and the blade heats up the beans by repeatedly striking them in the grinding process and it does have an affect on the quality of the coffee.
The burr grinders come in two types... the wheel and conical. The wheel burr grinder is less expensive but tends to be noisy. The conical is the best but is about twice the price of the wheel burr grinder. Here in the U.S. a good cone burr grinder costs about $325 for a really good quality... which is about twice the price of a whell type... Blade grinders are quite inexpensive... perhaps about $30.