Execution order in complicated queries
You should look at the execution plan for the exact order. As the plan depends on heuristics based on indexes, statistics and the like, you can't tell simply from the query.

So hit Ctrl-L in SSMS and look at the execution plan. Each operator calls the one on its right, requesting rows as needed.

The physical order in the execution plan may be quite different from the logical order expressed in the query. Itzik Ben-Gan has a good flowchart.