Okay let's look at the alternatives:
1. The best possible technique that can be used here is ASP.NET Sessions, which enable you to keep track of a user session while he/she navigates through your website. You can store the information in session object. Take a look at this article Exploring Session in ASP.NET
2. you might also want to work with cookies directly, storing information obtained by the user on the user's machine through cookies and whenever the same user comes back on the same page, then retrieving the values from the cookies if present on the machine. You might start by going through the article present at Beginner's Guide to ASP.NET Cookies
Hope that helps.