Collecting 'high paying client' ($500- $2000) Contact details ? - suggestions??

(say they are already on your list, and you want to add them to another form, to capture many of their details)
name, skype id, email, country,

Say within the next 1-6 months will be building a list of high ticket item clients, who you will be promoting services/packages between $500 - $2000, and you want to add them to another form, to capture many of their details) name, skype id, email, country

but want to use something instead of the aweber form or getersponse

due to any of these issues
-unconfirmation subscriber issues
-email ending up in the junk folder
-undeliverable of emails 1, 2, 3 etc
-any other issues which might occur with aweber or getresponse,

So you want to communicate with these high ticket item customers who are interested in using your service ,then what other alternative (and more efficient) ways are there to capture their details, such as
-name,
-email address
-country
-telephone number

I mean, like a service which is more efficient to contact them, when we use their service, (and I know nothing is 100% efficient)

Does anybody add more forms on aweber, collect their skype, country, tel number etc, and email/contact each contact manually?

Edit: Let me clarify one thing:
They are not in the process of buying them, but will be promoted these services in them price ranges... via marketing.

In other words, customers who wish to be promoted $500 - $2000 services (which many might say no to anyway )

they are not customers yet, but will be offered the services, who might be highly interested in the services, so want to capture their details, without losing them.
(before them paying, or before them deciding to pay- at the warming up stage, of them deciding to buy)