HI,
My would be wife is working in US on L1 Visa.
Soon we are getting married, I would like to go with her as dependent.
Can any one please let me know all the requirements.
She will not able to change her Surname because she need to change her name on Passport also which will take long time.

After you are married, you apply for the L-2 visa.

Check the consulate website for NIV application details, but you will need the visa application forms (DS-160 etc.), photos, a passport valid for at least 6 months, your marriage certificate and your wife's passport with her L-1 visa, the I-797 approval notice and her I-94.

And remember, after you enter the US as an L-2, you can file for an EAD. Takes about 90 days. Congratulations and good luck.