Just came across this handy website with low airfares to Belize: http://researchbelize.com/

I'll quote today's contents:
Originally Posted By: Research Belize
$358 MIA Miami International Miami USA 12/24/09 06:12
$372 BWI Baltimore Washington International Baltimore USA 12/24/09 01:22
$372 DEN Denver International Denver USA 12/24/09 06:03
$372 JFK John F Kennedy International New York USA 12/24/09 02:10
$372 LGA La Guardia New York USA 12/24/09 05:26
$372 EWR Newark Liberty International Newark USA 12/24/09 06:18
$372 TPA Tampa International Tampa USA 12/24/09 05:09
$372 IAD Washington Dulles International Washington USA 12/24/09 06:09
$376 PIT Pittsburgh International Pittsburgh USA 12/24/09 05:13
$403 DFW Dallas Fort Worth International Dallas-Fort Worth USA 12/24/09 04:17
$408 SJC Norman Y Mineta San Jose International San Jose USA 12/23/09 21:27
$412 SFO San Francisco International San Francisco USA 12/23/09 18:16
$419 MCI Kansas City International Kansas City USA 12/24/09 05:25
$432 ORD Chicago Ohare International Chicago USA 12/24/09 05:06
$432 PDX Portland International Portland USA 12/24/09 09:28
$439 GRR Gerald R Ford International Grand Rapids USA 12/24/09 06:20
$442 BOS General Edward Lawrence Logan International Boston USA 12/24/09 02:24
$445 LAX Los Angeles International Los Angeles USA 12/24/09 07:30
$452 SEA Seattle Tacoma International Seattle USA 12/24/09 05:07
$453 CLT Charlotte Douglas International Charlotte USA 12/24/09 06:06
$453 PHL Philadelphia International Philadelphia USA 12/24/09 04:15
$467 SLC Salt Lake City International Salt Lake City USA 12/24/09 06:04
$470 MSP Minneapolis St Paul International Minneapolis USA 12/24/09 06:15
$472 SYR Syracuse Hancock International Syracuse USA 12/24/09 02:17
$475 CLE Cleveland Hopkins International Cleveland USA 12/24/09 07:18
$478 IAH George Bush Intcntl Houston Houston USA 12/23/09 18:32
$483 BUF Buffalo Niagara International Buffalo USA 12/24/09 04:12
$492 SNA John Wayne Arpt Orange Co Santa Ana USA 12/24/09 01:16
$497 PHX Phoenix Sky Harbor International Phoenix USA 12/24/09 01:08
$523 SAN San Diego International Lindbergh Fld San Diego USA 12/24/09 06:17
$532 MSY Louis Armstrong New Orleans International New Orleans USA 12/24/09 06:07
$533 DTW Detroit Metro Wayne Co Detroit USA 12/23/09 18:29
$536 TUL Tulsa International Tulsa USA 12/24/09 06:01
$543 FLL Fort Lauderdale Hollywood International Fort Lauderdale USA 12/23/09 20:13
$550 LAS Mc Carran International Las Vegas USA 12/24/09 02:07
$555 BNA Nashville International Nashville USA 12/23/09 21:30
$556 ATL The William B Hartsfield Atlanta International Atlanta USA 12/24/09 06:14
$564 YYZ Lester B Pearson International Toronto Canada 12/24/09 05:16
$574 SMF Sacramento International Sacramento USA 12/24/09 06:05
$587 OAK Metropolitan Oakland International Oakland USA 12/24/09 06:10
$599 YUL Montreal International Dorval Montreal Canada 12/24/09 05:24
$617 CVG Cincinnati Northern Kentucky International Cincinnati USA 12/24/09 01:25
$632 MEM Memphis International Memphis USA 12/24/09 06:08
$644 YVR Vancouver International Vancouver Canada 12/24/09 08:02
$662 LHR Heathrow London England 12/24/09 06:22
$679 YYC Calgary International Calgary Canada 12/24/09 00:19
$1167 LGW Gatwick London England 12/24/09 07:29
$1578 BOI Boise Air Terminal Boise USA 12/6/09 22:09
$1697 BHM Birmingham International Birmingham USA 12/6/09 22:08
$1710 AUS Austin Bergstrom International Austin USA 12/6/09 22:06
$1976 ALB Albany International Albany USA 12/6/09 22:04

Lowest Fares Through 7/6/2010Last Updated 12/24/2009 9:32
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