In reply to Simon_87:
I actually started out in the High Atlas, but it was on a guided trip. However, to me it would be the perfect "first trek", and cheap and easy to do, whilst still feeling a world apart from Europe. You don't need a guide, but may or may not want to hire a mule/muleteer at least, to carry your gear.
The Toubkal area is the most popular, and the route up and down a bit too busy, but its still quiet off that route and the area is studded with little villages which can be strung together to make circular routes. Our route started at Imlil/Aroumd, and then over the passes Tizi n'Tamatert and Tacehddirt, before looping round to Oukaimede, Imesker and then west over the road to another valley system and villages who's name escapes me before back to Aroumd. This took a week at a medium pace. Stayed in the "village houses" which are basically simple hostels.
We then finished with a Toubkal ascent over 2 days, with a night ascent to reach the summit at sunrise, which was truly spectacular.
I was far more impressed with the Atlas than I expected, they really did feel like a big range of mountains in an exotic country.