not sure with your country is....
but since you already full of preparation, then i guess middle of July would be the perfect time for you to give
test.
you can now go to buy voucher exam of SCJP (eg: 310-035 or 310-055, depends which exam you giving for). and then register in prometric center(www.prometric.com), choose the nearest center with your area, and then set the time and go for it.
about where to buy voucher, i'm not sure about india, so hope other members here from india would help you by reply your post. for me personally, i from malaysia and i buy voucher in Sun Office located in KL.
all the best.