XML, ADO.NET, and XSLT

Perhaps a lot to bite off. I've solved most of the component problems in getting this to work but am unsure about how to put it all together. Here it is:

I have template.xml which has instructions about the data it contains - a simplifed example:

Code:

---

<SomeInstructions>text</SomeInstructions>
<Records/>
<SomeMoreInstructions>text</SomeMoreInstructions>

---

What I want to do is take the dataset I have in my form, write it to the empty records tag and then apply an XSLT sheet to output HTML. I already know how to do the transform from the original template.xml (w/o the records section) to HTML, but I'm a bit stuck on how to incorporate another XML source.

Any help? Thanks.