Need documents from 1599

What is the name of the particular document? If you can't find it try contacting your university librarian, they may be able to help. You may even have a librarian specifically for English or History students that can help you find the document or where you may be able to get hold of it. To be honest, being a document that old, I would have thought it wouldn't be easily publicly accessible and probably in a museum lol.

I'm doing my 2nd year research project for English and need a document from around this era to show public opinion of Queen Elizabeth, but I'm struggling to find any links to anything similar. Any historians know a source online?

Finding 'public opinion' in the sixteenth century can be tricky and much of what you will find is political treatises/ambassador's opinions/dedications such as that at the start of Spenser's Faerie Queene (though sometimes views from other areas of the social spectrum do survive).
Your best bet would be to start with a secondary source that pulls together the sources and references them. There is a book called "Queenship and political discourse in the Elizabethan Realms" that might be worth a look as it seems to have a chapter on perceptions of Elizabeth. Otherwise find a biography of Elizabeth and look at the chapter on her later years. It is unlikely you will find a document exactly from 1599 but there will be ones from around that time. Printed political treatises etc have sometimes been digitised - google search is pretty good at turning them up, sometimes freely available and other times it will depend on what subscriptions your university has.