Over at the new web design, web development and entrepreneurial resource, Vitamin (which looks great BTW) Jason Fried has posted a nice post about getting work done.
One tip to help you create some alone time is… Set up a rule at work: Make half the day alone time. From 10am-2pm, no one can talk to one another (except during lunch). Or make the first or the last half of the day the alone time period. Just make sure this period is contiguous in order to avoid productivity-killing interruptions.