If its tent sites you're looking for Anahiem Harbour RV has 2 sites. I have one booked in mid August. The shuttle goes thru every half hour. If you do a search I posted about this also (maybe 2 months ago). Good luck.
Disneyland is in the middle of a huge metro area. This is wall to wall streets, buildings, freeways, etc. Anaheim Harbor Rv Park has some tent sites, they are $40. For that price, you can probably find an inexpensive motel.
You may want to check on places in California State Parks near the ocean.