In addition to browsing through the entries on my help site that focus on paragraph structure, which you can find by clicking on the Writing Process category on the right sidebar, you might also take a look at these web resources:
- Paragraphs and Topic Sentences (from Indiana University’s Writing Tutorials)
- On Paragraphs (from the Purdue OWL)
You might also find these resources helpful, although they cover more than just paragraph structure:
- What is an academic paper? (from Dartmouth University Writing Program)
- The structure of college writing (from the Nuts and Bolts of College Writing guide)