Is there a way to edit a pdf with C#?

Look at iTextSHARP. It's a .NET library for manipulating PDFs.

It is definitely possible, but not with what is built-in to .NET (unless you are a PDF format guru and can roll your own). I've mostly used Aspose for manipulating PDFs, but there are a lot of toolkits out there. Personally, I think Aspose is a little rough around the edges but not moreso than other kits.

Well there's iTextSharp : http://sourceforge.net/projects/itextsharp/ with which you can write pdf files, but I don't think it has editing (reading pdf) capabilities, or they will be limited. I've never found a way to edit PDF's, unless you buy some third party tool ...