Hi there! Newbie-ness really isn't too much of a problem. Just keep things simple and remember that although technology changes rapidly, most of the recent "improvements" are in computer controls and optical coatings.
For nebulae and galaxies, try to stay around an F/6.3 focal length. It provides a wide field of view and decent power. Planetary observation and splitting double stars would benefit from the higher power of a scope around F/10.
Used scopes can provide a good value for a beginner. Some great scopes were built in the '60s and '70s and still work well today. A 6" F/8 Newtonian reflector (Criterion Dynascope RV-6) on an equatorial mount with a motor drive should cost about $500-600 US. It's large enough to be able to see faint objects with good magnification, but not "so much" as to be overly complicated or excessively bulky or heavy. Another choice might be an Optical Craftsmen 4.5" or 6" Newtonian. A 10mm, 18mm, and 26mm eyepiece set should get you by for a while. They might push your budget a bit. Get good eyepieces.
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I've met Don and bought my first recent scope (F/8 RV-6 ) through him. He ships world-wide.
Try and stay with an F/8 or F/10 focal length for Newtonian scopes to prevent adverse optical effects (coma).
Refractors provide very sharp images, but tend to be lengthy. Large refractors are very expensice and can be very heavy.
Any Cassegrain-type scope will likely get expensive quickly. Small new ones like the Meade ETX-90 are "ok", but you are sacrificing optical "quality" (aperture size and focal length) for spiffy electronics. A Meade Nextar4-GT lists for $999, but sells for about $425 on amazon.com. Something to think about. You won't get the light-gathering power of a 6" mirror, but it's a decent compromize on a budget.
If electronics are not a primary concern, you can save hundreds by using a star chart and moving the scope manually or with an AC-motor drive, and thus one can put more money in the scope's optics. Polar mounts with a single AC-motor drive are fairly inexpensive (check out Teletrade's catalog). This might be tricky in the UK with an American scope due to the voltage and AC mains frequency difference. Some drives can be used with a car battery - then it's no problem.
Hope this helps!