Is Appraisal Letter Of Any Value?

Hi All,
I am currently working as a Analyst in a company in Delhi, and recently have been offered employment in other firm.
I have all the documents from the employer namely, Offer Letter, Appointment Letter, Salary Slips, Exp. Letter(that I will get after my resignation). What I don't have is a appraisal letter.
And my company is just delaying the appraisal from last two months, and denying me the appraisal letter. Please suggest me what can I do in such scenario?
1.) Should I sue my company for not providing me the letter? Is it possible?
2.) Second way, a kind of risky too, can I make a self edited appraisal letter? Is it verified by the company?
Please suggest me which path to take?
Thanks

Dear Nikhil,
Let's understand why would you need an Appraisal Letter, You would need it as a proof to your new designation and the salary hike.
Are there email communications mentioning the appraisal? Does you new designation reflect along with your employee id in the ERP? How much have the hike changed your salary? Would you salary slip or even bank statement reflect that?
I suggest you collect the supporting documents and present it to your prospective employer. Please don't get into a case while exiting a firm. You need a clean comment from them in your back ground verification.
Please correct me in case I am wrong in my understanding. Looking forward to discuss this problem further with you.

""1.) Should I sue my company for not providing me the letter? Is it possible?
2.) Second way, a kind of risky too, can I make a self edited appraisal letter? Is it verified by the company?""
When did the company conduct appraisal for you?
Your two suggestions are impractical and creating a fake appraisal letter will go against you.
Talk to the management and see about appraisal.