'Tis the season of recommendations...

[SckizoBoy]

I'm after some fantasy/sci-fi fiction...

However, there is a catch: epistolary format.

The only two I know of are Dracula and World War Z (though the latter is not strictly speaking 'epistolary' though I'll count it).

 

[Rawne1980]

Why can you not just read normal novels damn you Skizo. Now I have to try and make my brain work....

Bloodline is the "sequel" to Dracula that's similar to what you are looking for.
Mary Shelly's Frankenstein.
Carrie.

Yes, I know technically they are more "horror" than fantasy/sci fi but you limited what you are looking for and I haven't read a great deal of books like that. Well, not many I can remember.

Memoirs of an Invisible Man.


The only other one I can think of is a Warhammer 40k book, Eisenhorn. It's written from the first person but has some epistolary content.

I've read a couple of books that were diaries but can't for the life in me remember what they are called. I'll have to go through my collection and find them so i'll mention them later.

 

[Queen Michael]

Flowers for Algernon is good.