The Tu-144LL wasn't looking very flight-ready in these photos
(Photo 1) (Photo 2)
They were taken by Aktug Ates during the MAKS aviation show in August, 1999 at Zhukovsky.
Here are some additional cockpit photos of the "LL". The date of the photos is unknown,
though an instrument is missing from the lower-left panel in these photos as it is in the 1999 photos above.
(Left side of cockpit)
(Right side of cockpit)
The Tu-144LL was offered for sale by an American firm in May, 2001. Suggested bids are US $10M for a flight-ready configuration or "seven figures" for a static configuration. Information can be found at this site.
Here are a number of NASA sites describing the Tu-144LL project.
Overview with description of tests to be performed.
NASA technical papers. These are large files in PDF format.
Longitudinal Handling Qualities of the Tu-144LL and Comparisons with Other Large Supersonic Aircraft (44 pages)
...Handling Qualities...of the TU-144 (120 pages)
...Measurements From The Tu-144LL Structure/Cabin Noise Follow-On Experiment (102 pages)
Low Order Equivalent System Identification for the Tu-144LL... (11 pages)