To be honest there are few alternatives to ADSL that are really adequate. This is not to say that ADSL is the best solution, but perhaps the only solution at this stage.
Via wireless there are several services, Sentec’s - Mywireless, WBS’s – Ibusrt Service, Vodacoms’s - 3G service to name but a few.
The problem here is twofold, most of these services operate only in flagged grid, in other words if you step out of the grid then you have little or no connectivity (defeats the object of wireless)
Secondly all bandwidth ultimately routes though our monopoly (TELKOM) at some stage anyway, so your alternative option is not so alternative.
Here is my advice, Take ADSL (its K@K – but the best of the worst for many) and DO NOT commit to any long term contracts – things are changing fast, rather pay for a router than commit your life to a service for the sake.
Trust this helps.