Hello bujji1976,
I applied for my wife's spouse visa on 9th April. Although the guidelines and support center say pay the Immigration Health Surcharge (IHS) along with the application, there is no link on gov.uk to pay the IHS. At least I couldn't find one. Neither did the VFS center where application was submitted said anything about paying the IHS to them, they only charged the application fees.
On 8th May we received email from
NEDELVisaInfo@fco.gov.uk asking us to pay the IHS through an embedded link. Followed the link, payed the IHS, replied to email with payment reference and got the visa confirmation the next working day. I think, contrary to the guidelines, they will only ask you to pay the IHS if they intend to grant the visa, or else they will have to issue a refund if they refuse the visa application. They haven't thought this one through, as with a lot of other guidelines, and just started asking for monies.
Suggest if you are submitting through a VFS center confirm with them and submit, or post application and wait for the email.
Good luck!