Its free plan lets you convert 25 files per day, and each file is given 5 minutes of conversion time. I guess the limit is satisfactory. Use this link to open this ePub to PDF converter tool.

even more important is that you can now tap a link to a .epub file in Safari and use the Open In interface to open the file in iBooks. Basically, forwarding books bought / downloaded in Mobile Safari ...

To open Linux Journal epubs purchased in the online store, we recommend using DropBox to sync up your eBooks books across devices, and download them to the iPad that way. Once you download each epub ...