These were more than just TSB's, the were "campaigns" (recalls). The third one was for new fuel rails to be installed as the old ones could begin to rust.
You should be able to regiser your GS at lexus.com, and look to see if your car qualifies, and look at its service history to see if these were done. Here's more information:
Special Service Campaigns (SSC)
SSC 9LA Certain 2006 2007 GS, 2006 2008 IS and 2007 2008 LS Vehicles Fuel Delivery Pipe Replacement
SSC 9LB Certain 2006 2007 GS and IS Vehicles Rear Brake Caliper Inspection
SSC 9LC Certain2006 2007 GS, IS and RX 400h Vehicles Electric Power Steering Link (EPS) Assembly Replacement
On January 16, 2009, Toyota filed a Defect Information Report (DIR) with the National Highway Traffic Safety Administration (NHTSA) regarding certain 2006 2007 GS 300/350, 2006 2008 IS 250/350 and 2007 2008 LS 460/460L vehicles. The involved vehicles are equipped with aluminum fuel delivery pipes (fuel rails). Lexus has determined that ethanol fuels with low moisture content will corrode the internal surface of the fuel rails. As this condition progresses the engine malfunction light (MIL) may illuminate. Over time, the corrosion will create a pinhole resulting in fuel leakage. SSC 9LA will be launched to replace the Fuel Delivery Pipes in the affected vehicles.
There are approximately 43,700 GS 300 (24,500 2WD, 19,200 AWD), 23,700 GS 350 (14,000 2WD, 9,700 AWD), 85,800 IS 250 (54,000 2WD, 31,800 AWD), 24,900 IS 350, and 36,400 LS 460 (25,500 LS 460, 10,900 LS 460L) vehicles involved in the U.S.
Additionally, Lexus is launching two other SSCs.
9LB Certain 2006 2007 model GS and IS vehicles to inspect rear brake calipers. On certain Lexus vehicles, the slide pin in the rear brake calipers may not operate smoothly. If the vehicle continues to be operated under these conditions, the brake pads may make noise.
9LC Certain 2007 GS 450h, 2006 2007 GS, IS and RX 400h vehicles to replace the electric power steering link (EPS) assembly. Certain vehicles may experience a noticeable gradual increase in the steering effort necessary at low speeds when turning the steering wheel to the complete left or right position. This condition may be most perceptible when parking the vehicle.
A dealer package including vital information and reimbursement procedures will be sent to dealers (to the attention of the service manager) today.
Lexus will inform owners of the involved vehicles with a Special Service Campaign notification letter sent via first class mail beginning in late January 2009.
All customer inquires should be directed to the Lexus Customer Assistance Center at 1-800-255-3987.
If you are a dealership associate and have any questions, please contact your District Service and Parts Manager.