Depends on where and when you want to go.
We never book "package holidays" always flights and accomodation seperate as it works out cheaper for us
We did a five night break at keycamp spain (2 adults and 5 kids) for about £400 Inc flights in September a few years back...the kids had a ball.
So its worth checking out any special offers they have.
We always use Ryanair for flights and they are cheap and no frills. Have managed to get 1p flights with them previously.
RE Accomodation, We often decide where we want to go then book flights in advance and try to get last minute deals which is when cancellations come up really cheap.
We have stayed in apartments, villas & hotels.
We managed to get a really good deal on a complex in spain for july (summer holidays) 2 years ago, cost about £300 S/C because it was listed allocated on arrival.
When we enquired with the holiday company they told us that they only use one hotel so this would be the same one listed as named accomodation for £500+.
We paid £30.00 each for a flight (5 of us) so worked out 1 week in the summer holidays for £450
We never usually book through a holiday company or travel agents, We search internet sites that private owners adverise on.
Cheap holidays can be done, but you have got to do loads of searching and research, Ie holiday reviews, checking location, area etc, to find them.
HTH