1. Click Queries
2. Select a category that you want to store this query in (Ex: Base)
3. Click New Query under the Tasks menu
4. Name the query
5. For Starting Query select Category: Base and Query: All Constituents
6. For the Data Return Type select Accounts
7. For Criteria Matching select Match Each Criteria
8. For Criteria select 'individual Transaction received'
9. Enter greater than or equal to 1.00
10. Save and Preview

The preview screen will show you the total number of results, which will be the number of accounts who have donated.