UK based newbie's thoughts and questions

Ok, to be honest it's mostly going to be questions, but hopefully fairly insightful and direct questions, not "how duz i makes money on the interwebz". I primarily make micro niche sites, rank them in google for adsense and affiliate sales income. I have had limited success, I'm a newbie. I have invested a mere £20 and so far, in 3 months have made £50 or so. Not great, but I've covered my costs and learned from my mistakes.

I'll preface this first by saying I'm based in the UK. From the research I've done, the numbers seem to add up differently here. In the US and Canada, where I presure most people on these forums are from, you have a farily large "local" userbase, 300 million people in the US alone, to visit your site, and click on you're ads/affiliate links/purchase you're product etc. UK more like 60 mil.

Ok so first question, say I have a .com that is hosted on a UK server (I use free hosting for my sites at 000 webhost, which seems to work ok for me) if an US based user searched for my targeted keyword, would they get my site displayed in their search results, with the same authroity it would in the UK? Or phrased a different way, does hosting location affect google rankings?

Next question. Why do article marketing? I've read a lot about it but not tried it yet. I'm going to create a linkwheel with article for some of my new sites, but I have a few questions. Who the hell reads articles? I am a veterain internet user, and I have never in my life, searched for something, been linked to ezine or whatever, and read an article. Is it merely for backlinks with a contextual content page with an anchored back links?

I'll slip in a though here so I don't seem too greedy .info's are useless for google rankings. I have done a lot of searching and found no definitive answer, so here we go. My first website was a .co.uk. It has made by far the most money, ranked high after a few weeks. The last batch I bought was 3x .info. They never ranked after 2 months. Similar competion, similar subject, similar site layout and content. .com and .co.uk seem to be on equal footing, not tried .net or .org. Hope that helps someone, I wasted money with those domains and I will never buy another .info unless i'm buying traffic or cpc.

Can someone explain social bookmarking and pinging for me. I have struggled to find much information. From what I can make out, social bookmarking is going to a social networking site, face book for example and linking you're site in a status update, for a backlink. I may be wrong but that how it seems. I just do not understand pinging though. I know what a ping is, I work in IT, but I don't understand the process or benefit of pinging a wordpress post. A basic explanation would be helpful.

One last question, can you serve different java code based on geographical location. I use easy content units for some price comparrison sectsions on my sites. This stops my sites looking like made for adsense sites and also, has earned me £20 in affiliate commission, not bad. Bassically, If I get a us visitor to my site, can I displayed a unit with links to US affiliates and a UK user UK based affiliates?

I know it's a lot of questions, but I would think most noobies struggle with these questions too and would be beneficial for a lot of people.

Also if anyone who is even more new to this than me and has any questions, they think I could answer for them go for it, I'll do my best.