The D&D 3.5e rules for death of a wizard’s or sorceror’s familiar are very, very harsh.

From the d20 SRD:

If the familiar dies or is dismissed by the sorcerer, the sorcerer must attempt a DC 15 Fortitude saving throw. Failure means he loses 200 experience points per sorcerer level; success reduces the loss to one-half that amount. However, a sorcerer’s experience point total can never go below 0 as the result of a familiar’s demise or dismissal. A slain or dismissed familiar cannot be replaced for a year and day. A slain familiar can be raised from the dead just as a character can be, and it does not lose a level or a Constitution point when this happy event occurs.

The permanent XP loss is so painful as to be avoided at all costs, which might be why wizards and sorcerors don’t pay much attention to their familiars.

A class feature that no-one ever uses is a broken class feature. Therefore, I have house-ruled the rules to be as follows:

If the familiar dies or is dismissed by the sorceror, the sorceror is nauseated and frightened for one day.

Succeeding on a Fortitude save reduces the nauseated effect to the sickened effect. Succeeding on a Will save reduces the frightened effect to the shaken effect. The Fortitude and Will saving throw DCs are equal to 15 + 1/2 character level (round down.)

Creatures which are immune to fear automatically succeed on the Will saving throw, and are always shaken.

A slain familiar can be raised from the dead just as a character can be, and it does not lose a level or a Constitution point when this happy event occurs.

The penalty is still severe - being nauseated and frightened for a day will instantly make the sorceror ineffective in combat. However, the penalty is not permanent, which means that familiars are no longer a huge liability in combat.