Yes...If your sole interest ids not just experimenting with overclocking thensimply buy the highest speed processor you can afford!
Overclocking is extra work... it is extra money (cooling), ....it is stressful.......and it can be wonderfully fulfilling, but, if it is not the main purpose behind your build, then go with stock now...enjoy your upgrade for awhile and then later if you feel it necessary ....
overclock the heck out of it!
Realistically you wont notice a huge difference in day-to-day speed from your average overclock, once your talking about 2000+ XP's and higher CPU's.
Plenty of other bottlenecks to worry about!