A plug, if I may: please have a look at the power attack spreedsheet on my site. Here's the link and verbage therein.
http://www.geocities.com/frisbeet/DandDandFightin.html
http://www.geocities.com/frisbeet/DandDandFightin.html
The 3.11 MB zipped Excel spreadsheet compares the average melee attack damage/round of a 3.5 Edition Dungeons and Dragons character, wielding his or her choice of Player's Handbook (PHB) weapons, inflicted against armor class values 10-50. The "comparison" worksheet is the only one not hidden, and is where the character and weapons may be parameterized; these are the yellow fields.
The spreadsheet also determines the optimum Power Attack value which maximizes the average damage/round
Nearly all combat feats and class inherent abilities from PHB, PHBII, Complete Warrior, Complete Adventurer, and Miniatures Handbook directly affecting melee attack roll, damage, and # attacks are included in the calculation and can be selected as desired. Many additional feats and prestige classes offered in core and supplemental resources can be exactly modeled in the spreadsheet with proper parameterization. The opponent's Damage Reduction and immunity to critical hits, attack modes Standard Attack and Charge Attack, and number of Attacks of Opportunity can also be selected as desired.
Please download the spreadsheet and modify it as you see fit. To view its brains, you'll need to "unhide" the other calculation/compilation sheets by selecting Unhide from the Format-Sheet dropdown menu. Future updates/corrections made by me will be implied in the file name as a version suffix > 7, and will also be annotated below.