MidgetDwarf, I'm not sure exactly what you are looking for - there are a wide variety of treatments of the subject. If you have access to a university library I would start browsing what you can find to see what works for you. I will comment on a few books:
The book Jack476 recommended,
https://www.amazon.com/Differential-Equations-Scientists-Engineers-Mathematics/dp/048667620X/ref=pd_sim_14_25?ie=UTF8&dpID=51E3CENO4SL&dpSrc=sims&preST=_AC_UL160_SR104,160_&refRID=0K3FNWGKYZJCC2RN925Q
is the simplest book I have ever seen on the subject. It is nice for getting some of the basic idea, but has almost no theory of any kind. I really like it, and for a quick first look over a winter break it would be comfortable to read and do problems from. Farlow is the PDE equivalent of the easiest calculus book you can imagine. If you primarily want theory it is not for you.
According to the preface, the book by Brezis assumes a knowledge of real analysis at the level of Royden's book, so you are unlikely to benefit from that level of treatment. I could of course be wrong, but certainly do not buy it without a chance to look through it first. You can see a preview on Amazon:
https://www.amazon.com/dp/0387709134/?tag=pfamazon01-20
If you are interested in applying PDEs to physics type problems, I Iike the book by Haberman, which is good with explaining techniques and has significantly more theory than Farlow.
https://www.amazon.com/dp/013263807X/?tag=pfamazon01-20
There are many other resources, of course. Again, check the PDE section of your library if possible. If you are looking for a more applied approach some "advanced engineering mathematics" or "math methods for physics" type books may help. good luck.jason