Here are the checked baggage rules of different airlines.
American
1st-$15
2nd-$25
Continental
1st-Free
2nd-$25
Delta
_TRAVEL IN USA
1st-Free
2nd-$25
3rd,4th,5th-$80 each
6th,7th,8th-$110 each
9th,10th-$180 each
_TRAVEL NOT IN THE USA
1st,2nd-Free
3rd,4th,5th-$150 each
5th,7th,8th-$300 each
9th,10th-$600 each
Southwest
1st,2nd-Free
3rd-$25
4th,5th,6th,7th,8th,9th-$50 each
10th±$110 each
United
1st-$15
2nd-$25
Alaska
1st-Free
2nd-$25
3rd-$125
Air Canada
1st-Free
2nd and so on-$125
Northwest
1st-Free
2nd-$25
3rd,4th,5th,6th-$100 Each
US Airways
1st-$15
2nd-$25
3rd,4th,5th,6th,7th,8th,9th-$100 Each
You can post any changes in these rules,updates,or new rules.
You can also post the carry on baggage rule and Missalaneous airline charges.