Can some bosy tell me what questions are asked for webMethods interview or suggest a site for the same.
Also please tell me the difference between webMethods 4.x, webMethods 5.x and webMethods 6.x

This is the best site for finding out information about webMethods. Interview questions will be very much like interviewing for any other technical position: questions about your background, your experience with the technology and with other technologies, etc.

Note that webMethods is capitalized in a unique way–and that it is the name of the company, not the product. Saying that one understands webMethods is somewhat like saying one understands Microsoft: its a bit ambiguous because there are many products.

Hello,
One good thing to note is that 5.x of Integration Server as I have heard is not a publicly used product in the mainstream. The jump most everyone has seen was from 4.6 -> 6.0.1 -> 6.1 and having all the service packs to stabilize things. And besides this site, the advantage site @ advantage.webmethods.com for www.webmethods.com is the site to learn things in a concrete “read the fine manual” manner. You may want to contact them to try and download a trial of the software or part of it so you can be hands on in understanding things you read. I hold this site in high regard as the place to go to for fast answers in practical terms and general talk of integrating. A final note, like Rob said, You should know that there are about 2 to 4 core products used in any given environment (Integration Server, Developer, Broker, Trading Networks) and they are not the rule of necessity but show up a lot. So knowing the summary of what these do is good for you.
Good day.

Yemi Bedu

Yemi,

There was a 5.0 release of the Broker-related products. When they unified the platform and the version numbers (6.0), they had to go directly to 6 because of the 5.0 Broker. The unified version numbers can be somewhat confusing; for instance, Workflow 4.6 was actually the first release of Workflow.

Tate