In terms of arranging a punt untraceably, obviously in person is generally safest (as in, walking into sauna), not many people use it in the uk, but voip (Internet voice phone call) is, I understand, slightly better that landlines and mobiles, especially if both parties are using it, Skype is supposed to better than other voips as it's encrypted (they say), at least assuming there are no backdoors on the computer you use for recording the conversation.
In practice, most prossies require you to carry a phone for incalls so they can tell you the address after you have left home. The simplest security might just be to add a password lock to your phone if you are not in the habit of locking it generally. The wife might be your biggest concern, but even if you use a disposable phone for punting, a vicious prossie or pimp could still get your previously called numbers and do some damage to your hobby. Deleting info from a sim card usually just hides it, not deletes it. Plug the thing into a computer and the data can be recovered with data recovery programs. Your wife is not likely to go to that trouble as it's expensive or too much hassle, but organised crime just might.
If you do use a smartphone, one risk is just costs (a cheap one is easier to replace). iPhones used to be more secure than Androids but I read that new measures are making them more even. Having lots of apps like shitware games (and not updating the firmware) increases the percentage risk ,not of automatic monitoring by security services since they don't need that sort of help, but it increases the chance of a criminal finding your deleted 'data' (hacking sites and usenet groups monitor that stuff as eagerly as we monitor prossie info).
I'm just saying it's like safe sex. The risks are different for everyone and each person should work out what they are individually. The biggest newbie mistake I think is still giving away too much personal information on forums.
