email slow sending

[byronyasgur]

hi - i am having problems with emails taking longish time to send ( have tried on a couple of different domains using outlook express and thunderbird) - a simple test email with one line and no attachment takes about 15 seconds after i press send.(interestingly i can see the email arriving at the recipient account before it has finished sending from outlook/tb !!) I have found several references to editing /etc/xinetd.d/smtp_psa on these forums so i was going to try that but when i navigate to that directory there is no sign of smtp_psa - i am using qmail, plesk 8.6.0 debian. has anyone got any ideas what could be wrong for me. I have very limited experience with webservers so i suppose i could be doing something stupid.
My host provider is farily reputable and so i assume that they set the vps up properly; however they are now saying that as it is unmanaged i am on my own so any help GREATLY appreciated