I'm a manager of a shop that sells fitness equipment...have you decided if you want to go upright or recumbent? Some people with knee issues do better with one over the other, it depends on the person. Somebody mentioned spin bikes, they aren't always the best way to go with a knee problems, due to the fact that they don't freewheel (you can't stop pedaling once started and allow the bike to "coast" like a normal bicycle for instance). This can put some added stress on the knees, especially for somebody that isn't used to it. Bodyguard and Lifecycle make some very good stationary bikes. Also look into SportsArt, they are an excellent company with a decent range of prices (I think $1100 to $2000 or so). If you are on a more limited budget, I've had pretty good success with upright and recumbent bikes from Hudson, starting at a much lower price-$600 or so, and going up to around $1300.00