ScienceBoy
Money List Winner
have a go with some on their simulator. Will at least give you a clue on length, shafts etc.
If you are average height, average build off the shelf is fine.
If you are over 6'4 or under 5'6 (ie out of average range) I would look into getting any clubs cut to fit to begin with.
No need to spend over £250 to get everything inc a bag to begin with. A decent bag is worth forking out for as it should last.