I don't really think them to be that confusing. But then, I played a wrestler in one D&D campaign and thus learned every detail of the rules. In Conan, with the Crushing Grip feat, grappling is one of the most potent combat styles available, toe to toe with Power Attack combined with two-handed weapons.
Read these all about grappling -articles, all of them and it becomes much more clear. If grapple value of a character is not simply BAB + Str bonus for some reason, write it down separately.
http://www.wizards.com/default.asp?x=dnd/rg/20050301a
http://www.wizards.com/default.asp?x=dnd/rg/20050308a
http://www.wizards.com/default.asp?x=dnd/rg/20050315a
http://www.wizards.com/default.asp?x=dnd/rg/20050322a
Things to remember after reading the articles I linked - though I'm still using AE, so these things might not be valid anymore in the Second Edition, if that is your preferred ruleset.
1) Wrestling characters can't dodge or parry attacks from other people not involved in the match - though if they try to stab each other with daggers or something, they can dodge each other. Maneuvers are exceptions, like one of my favorite maneuvers all time, Human Shield. Yes, this means that holding someone while the Zamoran cuts his throat is a very valid tactic, since he'll be vulnerable to sneak attack while grappling. Oh and if the intended target is using the other guys as a Human Shield, it is possible that the Zamoran thief sneak attacks him instead. Nothing funnier than friendly casualties by accident.
2) You can make an opposed grapple check to try to damage your opponent in a grapple. The damage received is the unarmed damage the character causes. Thus, if he has the Brawl feat or other ways to increase unarmed damage, it will be higher than otherwise. Keep this in mind. Crushing Grip is naturally an exception.
3) Light, natural and unarmed weapons can be used in grapple to attack, but it comes with -4 penalty to hit and the guy in the receiving end uses his full Dodge - he can't parry. You don't really need to know what light weapons are by definition, just play it by the ear - if it is a small weapon you could think of using in a wrestling match, it is or at least should be a light weapon.
4) In Conan, the concentration check to cast spells while grappled is 20 + PP cost of the spell. Defensive blast can be used as normal.
5) Shooting or throwing things in grapple without Improved Precise Shot confers 50% chance to hit other target than intended. In my current campaign one of the characters was grappling with a ghoul and another characters was shooting in the melee. He scored a critical hit and shot his friend in the eye.
6) While a character is pinned in grapple, the pinning person may prevent him from speaking. I've houseruled that with a succesful pin you can as well prevent the losing side from looking at you, thus negating Evil Eye spells, War of Soul and other things requiring eye contact.
7) Remember size differences. Creatures can only try to grapple things that are one size category larger than them. So a human could try to wrestle with a horse or a bear, but not with an elephant. However the larger creatures can decide to grapple things much smaller than them. Usually big things have so big grapple checks that the poor victims have no chance of getting away from the grip once it is established, unless they roll natural 20.