Posters aren't usually printed on glossy paper but an uncoated stock (at least here in the US)
How big is your poster?
What is 'low run'?
Depending on the size of your poster, finding a dedicated shop that uses digital printing rather than press would probably be more to your advantage. Even one with a high quality (high head dpi in the 600-720 range), ecosol or solvent printer would work.

Hi, well size ain't too much of a concern at moment but the min size would be A4 and Max around A2.... and qty being as low as 25 or so, some poeple can do Laser Print but that leaves the ink raised slightly if you know what I mean... I'm looking for a kind of print that normal posters would be in... and I mean Glossy as in there is a slight shine, not coated e.g you can get Super Glossy posters that are coated (not laminated) and then normal posters on a glossy heavy paper and then your normal paper which is just like printer paper

Is Digital print quality the same as Laser or better??, and what way does it appear on paper, e.g. does it have that same heavy raised effect that some Laser toner gives when you touch the paper??

I'm not sure I can help you, but I think I'm in the same boat as you, sort of.
I've been wanting to print my own postcards, but I am not sure if I can. You know the glossy paper that postcards (such as tourist potcards... glossy photo on one side, regular uncoated on the other (or glossy on both sides, doesn't matter)).... I don't know if I can find that kind of paper anywhere?
Or can I even print it at home on my inkjet? I prefer to do all my printing myself, but I'm not sure if I can. Does it HAVE to be offset printed?
Any help?

Sorry I can't help you Weecutz....

I know a place that prints Postcards with your Pic on one side and then the normal average layout on the other side... where are you in the UK or US or ???

The only problem is they MIGHT print their company logo on it somewhere??

Let me know

I am in Pittsburgh.... the US
I am always interested in finding out about places.... would much rather do it at home, but might not have a choice.

Just sent you a PM kovachjon

Anyone know anywhere that would maybe even do short run prints like "Promo Flats"??

Most of the regular posters you see are high run on either a press or screen printed. If you can find someone with an ecosol or a solvent high dpi printer (600dpi+ print head), a print on Rexam paper would be close to what you see in a high run poster. How much dithering you see depends on viewing distance, your image resolution (200dpi is highest I would go) and whether or not the printer really runs it at the slower, higher quality speed. You will definitely see dithering in a 360dpi printhead.

The ink isn't raised and does not crack like a laser print (unless there is a receptive coating on the paper that does crack. Ask to see samples).

I'd say a regular inkjet would work too but the inks are susceptible to water damage. Some people will do a spray coating on those though or an overlamination. Costs extra. Any one with an HP5500 could do a bang up job for you.

A2 or A4 are not very large and the machines I speak of are wide format (48"+). The posters would have to be ganged and trimmed by the printer (you submit only one). Don't forget to ask for specs on crops and bleed.

What are promo flats?

Maybe it would be in your best interest to check out some of the more affordable large format inkjets out there and print these yourself.
http://www.large-format-printers.org/

Promo Flats are Card Board 12"X12" Double Sided Full Colour (usually) album art printed on approx 300gr Cardstock.... I know that usually for this type of thing you'd need to order a load of em, but I'm looking for somewhere that can do similar but less qty... just looking about at the moment though

actually PD... I print posters here off my HP on a glossy stock. comes out really well (take a bit to dry though)