Perform an to [ABCD] conversion. If you have MATLAB, you can use the "s2rlgc" command. Otherwise, you can find the conversion formulae anywhere online.
Then, look up how to extract the propagation constant γ and characteristic impedance Zo:
A = cosh(γl), where l is the length of the TL; therefore, γ = acosh(A)/l.
B = sinh(γl)*Zo, C = (1/Zo)*sinh(γl); therefore, Zo = sqrt(B/C).
Then you can solve for Z = R + jωL and Y = G + jωC as:
Z = γ*Zo
Y = (1/Zo)*γ
Good Luck!