You can download a modern English version of The Faerie Queene at Project Gutenberg at the link pasted below.
If you'll give yourself a chance, you might find that Middle English, which is what Spenser used, is really not that difficult to read. Spellings are different, especially in the use of vowels. Whereas today we use the spelling "fairy," Spenser used "faerie"; we use "knight," and Spenser used "knyghte." Most words should be recognizable to you, and those that aren't are probably annotated in the margin or in a footnote.
Middle English is the in-between form of English--between the Old English of the Anglo-Saxons and the Renaissance English of Shakespeare. It is heavily influenced by French because of the Norman Conquest.
I've pasted for you below a link to How to Read and Speak Middle English. Follow those 7 steps--and have fun!