Advice needed - Contact form that can handle API

Hi there.

Need some advice on plugins to use. Tried some and on a dead end.

-Need a contact form that I can customize. (basic stuff)
-Want to integrate a service to send sms directly to client as confirmation once they complete the contact form.
-Some contact form plugins offer this already but don't have a carrier for South Africa.
-I currently use 2way.co.za services for this. Sample code below:

http://bulksms.2way.co.za:5567/eapi/submission/send_sms/2/2.0?username>=user&password=abcd1234&message=Hi+Mom+%26+Dad&msisdn=+27800000000

Any suggestions or advice?