Election dates:
Primary - Tuesday, June 3, 2008
General - Tuesday, November 4, 2008

Voter Registration dates:
Primary - Saturday, May 24, 2008
General - Saturday, October 25, 2008

From the Iowa Secretary of State web site:

You may register to vote if:

1. You are a citizen of the United States.
2. You are a resident of Iowa.
3. You will be at least 18 years old on or before election day.

NOTE: If you are 17½ years old, you may register to vote, but your registration will not be effective until your 18th birthday.

The Iowa Secretary of State has made the official voter registration available online in a pdf format:

English Voter Registration Form [1]
Español Aplicacion Para el Registro de Votacion [2]
Vietnamese Voter Registration Form [3]
Laotian Voter Registration Form [4]

You may print these online forms and fill out the one you need to use by hand. Please be sure to sign the form before you send it to your County Auditor.

Click Here for a List of County Auditors and Their Addresses [5]

If you would like a hard copy of any of the forms above, please call the Secretary of State's Office at 515-281-5760 or 800-SOS-VOTE (800-767-8683).

The Secretary of State has also made the Application for an Absentee Ballot available on the web please print this off and fill it out and mail it according to the instructions on the form.

English Application for an Absentee Ballot [6]
Español Formulario Official Para Solicitud de Votación en Ausencia [7]
Laotian Application for an Absentee Ballot [8]
Vietnamese Application for an Absentee Ballot [9]

For more information, please go to the Voter/Elections Page on the Iowa Secretary of State Web Site [10]