Self-citations generally form a significant fraction of a scholar's citation total. Removing self-cites is important for acurately measuring individual scholarly impact.
By using some advanced operators you can remove self-sites from Google Scholar. Use "-author:" to take out papers written by a specific author. In practice this only works when looking at specific articles and you will have to select different name forms ("mccullough, ib" "mccullough, ian") for the best results. The utility of this functionality is highly dependent on the situation.
The strategy of searching full-text for mentions of your name, and then subtracting items authored by you, is sound in a variety of structured databases.