I find the cheapest way to do it is to book a flight only then use someone like
http://www.travelrepublic.co.uk or http://www.alpharooms.co.uk for your accomodation.
I always book my taxi transfer through http://www.canaryforum.com click the pic of a car on the top right for a quote.

Failing that just put your details into say thomsons, firstchoice or thomas cook www and see what they have coming up.

If you can fly from Gatwick easy jet now do Gran Canaria and have some ok prices depending on dates of travel.
Ive booked my flights for Aug with thomson as they were the cheapest at the time.

http://www.skyscanner.co.uk will give you flight prices for most airlines.

Going through the usual channels ie tour operators, Thomas Cook looks about the cheapest, leaving Luton on 25th for a week going to Lanzarote S.C, price for 2 adults and 3 children works out just over £1100 pounds, Flight only is not much cheaper even with Easyjet.
The only alternative to suggest is wait for a late deal, First Choice usually have good deals if you book a couple of weeks before departure.