The first thing you need to do before starting your TAIL-PCR is to figure out which border of the T-DNA is flanking the plant genome, especially with Ken Feldmann's lines since the concatameric nature of the T-DNA inserts. The best way to do that is to follow the procedure designed by Ponce et al, which was published in the Plant Journal [Ponce et al,(1998): Rapid discrimination of sequences flanking and within T-DNA insertions in the Arabidopsis genome. The Plant Journal, 14:497-501.
Primer sequences (working dilution: 50uM)

•  AD2: 5' NGT CGA (G/C)(A/T)G ANA (A/T)GA A 3' 、
•  OPA-2: 5' TGC CGA GCTG 3'  
•  T-DNA left border primer sequences (T-DNA left border sequences (working dilution: 50uM)  
•  TL-1: 5' CAG CCA ATT TTA GAC AAG TAT CA 3' 
•  TL-2: 5' AAC TGT AAT GAC TCC GCG CAA TA 3' 
•  TL-3: 5' TCT GGG AAT GGC GTA ACA AAG GC 3'  
   Genomic DNA extraction (CTAB method was used in my case, but it might be not essential).

Dilute the genomic DNA to 20ng/ul with water.

• To ease the pipetting procedure, a PCR stock solution was used (I found both the Perkin-Elmer's and Stratagene's Taq polymerases work very well, in condition of using their own buffers):  
   705ul water
   100ul 10X Taq polymerase buffer (Perkin's or Stratagene's)
   20ul 10mM dATP
   20ul 10mM dCTP
   20ul 10mM dGTP
   20ul 10mM dTTP  
• Primary reaction mixture for the TAIL-PCR  
   44ul PCR stock
   2.5ul TL-3
   2.5ul AD-2 or OPA-2
   1ul Genomic DNA (20ng/ul)
   Thermo-cycling: to, and then
   Cycling 92^oC; 5 min;[Add 0.2 ul Taq polymerase (Perkins-Elmer's or Stratagene's) after 4 min denaturation, link to clcling
   Cycling  (5 cycles of the following):  
   94^oC, 1'
   62^oC, 1'
   72^oC2.5'   
   Cycling  (1 cycle of the following):  
   94^oC, 1'
   25^oC, 3'
   Ramp to 72^oC in 3'
   72^oC2.5'  
   Cycling (15 cycles of the following):  
   94^oC, 30''
   68^oC, 1'
   72^oC, 2.5'  
   94^oC, 30''
   68^oC, 1'
   72^oC; 2.5'
   94^oC, 30''
   44^oC; 1'
   72^oC; 2.5'  
   cycling  
   72^oC, 5'  
   Cycling  
   4^oC. soak  
  
  
• Dilute the primary reaction product with water to 1/50, then set up the 2nd reaction
   44ul PCR stock
   2.5ul TL-2 (50uM)
   2.5ul AD-2 or OPA-2 (50uM)
   1ul 1/50 diluted 1st reaction