Notarial Records In New Orleans

I recently accessed the New Orleans Notarial Archives online here.
In February 2009 the archives was facing a looming financial crisis
(but are currently online).  The history of the New Orleans Notarial
Archives provides a good overview of this unique system.

In regards to finding property records:

"While there is no comprehensive index to the records, a companion
office to the Notarial Archives, the Register of Conveyances,
maintains party-name indexes to property transfers  back to 1827.  
The Conveyance indexes are annual, and are divided into "Vendor 
(seller)" and "Purchaser." The Conveyance indexes are extremely
useful in locating notaries – essential data in accessing notarial  records
created before 1970."

Below are two examples of items in the Notarial Archives:

Francisco Broutin
Notary Public
April 21st - May 31st 1798
Pages 1 - 270 Inc.
Court Proceedings
Book II
WPA

Clark, Daniel
vs. Estate of Estevan Burnel
re: collection of a debt
10 May 1798
8 107-111

There are also plan book plans, described as architectural drawings of
buildings in New Orleans:

"The drawings were created as legal descriptions and
advertisements of houses, lots and tracts of land offered for
sale at public auction."

Other Louisiana sources are listed here.