My favorite fighter build looks something like this:
Human Fighter 12
Stats: Str:16 (18) Dex:18 (20) Con:14 Int:14 Wis:10 Cha:8
Feat Selection: Quick Draw (1), Combat Reflexes (1), Dodge (1), Hold the Line (2), Mobility (3), Spring Attack (4), Elusive Target (6), Improved Trip (6), Power Attack (8), Combat Expertise (9), Whirlwind Attack (10), Close-Quarters Fighting (12), Improved Initiative (12)
Basic Equipment: +2 longspear, +2 greatsword, spiked gauntlets, mighty (+4 Str) composite longbow, +2 studded leather, ring of protection +2, belt of giant str +2, bracers of dexerity +2, cloak of resistance +2, boots of striding & sprining.
To Stat it Out: Human Fig 12; HD 12d10+24 (hp 89- average); Init +9; Spd 40; AC 22, t 17, ff 17; BAB/Grp +12/+16; Atk +18/+13/+8 melee (1d8+8 /x3, +2 longspear), or +18/+13/+8 melee (2d6+8 /19-20, +2 greatsword), or +16/+11/+6 melee (1d4+4, spiked gauntlet), or +17/+12/+7 ranged (1d8+4 /x3, longbow); SV Fort+ 12 Ref+ 11 Will+ 6; Abilities Str 16(18) Dex 18(20) Con 14 Int 14 Wis 10 Cha 8; Skills and Feats Craft+9 (9), Jump+11 (5), Climb+9 (5), Spot+7 (7), Listen+7 (7), Search+9 (7), Tumble+14 (7); Quick Draw, Combat Reflexes, Dodge, Hold the Line, Mobility, Spring Attack, Elusive Target, Improved Trip, Power Attack, Combat Expertise, Whirlwind Attack, Close-Quarters Fighting, Improved Initiative.
Idea: The basic idea for this character is a mobile fighter that rarely gets close enough to takes hits. Tactics differ against different types of encounters. Against smaller opponents and mass combats he works best to use combat expertise to buff his AC, and let opponents come to him. If they move up to attack or charge him, combat reflexes and hold the line allows him an AoO, which works perfectly with Improved Trip. He has Whirlwind attack in case they attempt to swarm him, or if he finds an ample opportunity to use it. When opponents come too close he drops the spear and uses his greatsword (remember that if he's charged he still gets an AoO due to hold the line). Against larger opponents he employs hit and run tactics. He will generally target them with his Dodge ability, improving his own AC while making himself immune to their power attack attempts. Spring attack is a must to avoid close confrontation, as he is not made to be a tank. Power attacks are also I nice option to wear the big guy down with big hit and run attacks. In case the big creature tries to grapple him, whether by the mouth, tail, claw (whatever), he gets a free AoO, and the damage dealt counts to his grapple check.