"θέλω" is the indicative so... I guess "I want" should be accepted right? (even if Greeks maybe use the indicative more often than we do in English?)
Yes, "want" is ok and "would like" is a little more polite. But both are accepted check the hover.
i want an item of information, please.. should also be accepted i submit
Yes, we haven't yet added it because it is a non-standard use of Eng. Much better is: I would like...
yes I agree, I have just been chatting with a Greek friend, who told me that θέλω doesn't sound rude, unlike I want in English.
Thank you for that. I was afraid I'd offended you by not adding "want" as I had originally said I would. I'm very glad to have you second my decision. Oh, and thank your Greek friend.
Informations is not used in English instead πληροφορίες is quite common in Greek. See the information kiosks in Greece, they have a label in Greek Πληροφορίες and Information in English :)
"information" is uncountable in English so it is never used in the plural and never has a number a/an, one, two etc*. You can say "some information" or just "information".
"would like" is translated as "θα ήθελα" however it's also used as a polite form of "want".