Hi you
Yes, you need to pass the EX200 and EX300 to attain the RHCE. You can pass the exams in any order, but you won't attain the RHCE until you've passed both.
I used the McGraw Hill "RHCSA / RHCE Red Hat Linux Certification Study Guide" and the "RHCSA / RHCE Red Hat Linux Certification Practice Exams" books by Michael Chang. Those provide ample preparation, provided you have already hands-on experience with RHEL.