Hi Richard and
Thats the big dollar question! but you dont need huge wads of cash to get the feel and ideas of what you want. Next month in Lostock is the IISAC
http://www.iceinspace.com.au/iisac.html, im very sure there will be people up there who would be more than willing to let you look through their telescopes.
First you need a budget and try to stick to it, otherwise it will spiral out of control and you will end up doing something silly like building an observatory.
Second, what kind of AP do you want to do? Planetary? DSO? Widefield? get all the relevant information on the type of AP you want to do before spending a cent.
Thirdly, Read some of the previous posts on "Which Scope" plenty of info to work from, you never know someone may have answered your exact question. here is one i found as a starting point
http://www.iceinspace.com.au/forum/s...=100795&page=2
Good Luck! and Clear Skies!