It may be genuine, but I will be wary of a website with no direct access to customer services, & the only way to contact them being an online form.
They're based in Belfast, not Jersey.
This is whois report:
Registrant:
BlackStar Associates Limited
21 Alfred Street
Belfast, Antrim BT2 8ED
UK
Domain Name: SENDIT.COM
Administrative Contact:
Young, Simon
@sendit.com
Sendit.com Ltd.
42 The Cutts
Dunmurry
Belfast, Northern Ireland BT17 9HN
UK
+44 2890 430430 fax: +44 2890 430460
Technical Contact:
BlackStar Associates Limited
@blackstar.co.uk
21 Alfred Street
Belfast, Antrim BT2 8ED
UK
+44 2890 509000
Record expires on 15-Mar-2011.
Record created on 04-Mar-2004.
Database last updated on 20-Jan-2010 15:31:11 EST.
Domain servers in listed order:
NS0.BLACKSTAR.CO.UK
NS1.BLACKSTAR.CO.UK
Information Updated: Wed, 20 Jan 2010 20:39:06 UT