Auditing:Extracting Changed Fields From Inserted Table

Hello,

I'm creating an audit table and associated triggers to be able to capture
any updates and deletes from various tables in the database. I know how to
capture the records that have been updated or deleted, but is there any way
that I can cycle through a changed record, look at the old vs new values and
capture only the values that have changed?

To give you a better idea of what I'm trying to do, instead of creating a
copy of the original table (some tables have many fields) and creating a
whole record if a type or bit field has been changed, I'd like to only
capture the change in a single audit table that will have the following
fields;

AuditID int INDENTITY(1,1)
TableName varchar(100)
FieldName varchar(100)
OldValue varchar(255)
NewValue varchar(255)
AuditDate datetime DEFAULT(GetDate())

Any direction would be greatly appreciated.

Thanks!
Rick