Plenty of places to stay on the Gold Coast. Been there a couple of times myself, its a great place to visit! I would suggest you avoid Coolengatta as it's way to far away from the Gold Coast itself (IE bout half hour drive).
My advice is you want to stay somewhere in central Surfers Paradise. Surfers is the main shopping/party area like Freo/Northbridge in Perth. Its pretty close to all the major touristy things like the theme parks etc and is right on the beach. When your looking for accommodation look to get as close as possible to Caville av which is the very heart of surfers.
There's a ton of hotels/motels/apartments etc available depending on whether your going to be going out every night or eating at home. I stayed at Mantra Circle on Caville, which is at the end of Caville av. Was an awesome place to stay we were on the 24th floor so had a great view of the ocean. That said its pretty pricey depending on what your looking at. Check out their website for pricing
http://www.mantracircleoncavill.com.au/
The previous time i stayed at Surfers International Resort Apartments. This place was again quite nice. It's a bit older in style but its clean and tidy the staff were really friendly and its right on the beach too. There website
http://www.surfers-international.com.au/index.ews
Asides from those two, do a search for accommodation on the gold coast and you'll find a heap of places. Only thing i would suggest is check out the reviews on them before you book. There's a few places I've seen where the website has made them look really nice and new when in fact there 30 odd years old.
If you need any more info or advice let me know!