For flights, I've found using
http://www.ba.com is a good way to keep a check on when the flight costs change. You can put in +/- 7 or 14 days on your planned travel date and it shows you the the cost for all the days around your intended one. It makes it much easier to work out if changing your plans a day or so may save you money.
For accommodation are you looking for just a hotel room or would you need something bigger? I've had a lot of luck recently picking up La Quinta Inn Lakeside through
http://www.hotwire.com for less than $40 a night. The hotel itself is a little older, but the rooms have always been more than adiquate, the pools are pretty good and it's in an excellent location. Using hotwire is always a bit of a gamble as you don't know the exact hotel until after you commit to the booking, but I've always been very pleased with the rooms I have ended up with. I just checked up and in October (middle) I found a 3.5* hotel at $50 a night, a condo style at $62 a night and a 2 bedroom condo style at $100 a night, all of which look a pretty good deal depending on what you're looking for.
Another possibility would be to keep your eye's open for the promos various timeshare companies offer. These often offer 3/4 night stays for a couple of hundred bucks, but you have to agree to spend an hour going through a promo. It means you have to set a side some of your vacation time, but they do bring out some pretty good deals at times. I recently saw one that offered 4 nights in Orlando plus 2 nights at Daytona beach PLUS a 4 day all inclusive cruise. I think the total (for a family of four) was GBP 400 . Here's a link to an example of just one of the offers, this one is Sheraton's Vistana resort.
http://www.starwoodresortcollections.com/2/prequal_svv.jsp . A 4 night package for $229 in a one bedroom unit that fits 2 adults and 2 kids. Do two different resorts and your rooms for 8 nights is going to cost you just 250 quid !!. Granted you'd have to give up a couple of mornings attending timeshare presentations and that's not everyone's idea of a fun time, but it is a good way to get cutprice great quality accommodation.