I suggest you first narrow down your cad platform first, as this is where the design will begin (assuming you will be using a seperate cad and cam setup).
Some cad programs do work particularly well with some cam programs. Solidworks, for instance, has a list of cam programs it suggests. I believe Feature Cam actually works as a plug-in in solidworks (it may work as a stand alone too). From my understanding, you don't even have to export from SW to FC. Once finnished designing, you can go straight to toolpaths. One cnc is another cam package suggested by Solidworks (visual similarities between the two are pretty apparent). Visualmill and Rhino 3-d are also partnered in a sense: Naitive Rhino files can be exported and opened in visualmill (no need to use .stl or .iges which can sometimes loose info in the translation). Furthermore, layers used in visualmill to define machining boundaries can be designated in Rhino before exporting, making life a lot easier. They have a forum at the mechsoft site you might want to check out
These are the only two I can think of right now. I hope this helps.
Edit: whoops. I didn't see your price limit. Maybe try the basic level of Onecnc. I'm not sure how good its cad is but I suspect its decent. Only problem is they don't give out demos. Only live online tours. Still worth checking out as its a very simple cam solution.