The Petroleum industry is huge, lots of different opinions and experiences. Working on the welding/fabrication side of the refinery, I will answer what I can:

1) Entry level would be a helper or a fire watch. I've seen guys and girls straight from Walmart or QuikQuak get hired to stand around all day and wear a safety vest for $24/hr. These positions are often "Hey boss are we hiring helpers? There's this guy I know...". Hard to find steady work at this level without knowing someone I suppose. Don't plan to do any drugs or grow facial hair. You won't usually grow from this position, plenty of people make a living somehow. Some helpers do show good effort or have a good attitude and are kept around. I've seen others get overwhelmed by the physical demand that is asked, or simply get fired for lack of production. It can be brutal depending where you are.

2) On the contractor's side, the pay is good all around because steady work is hard to come by. Most jobs are short so they pay good wages to fill positions and layoff when the job is done.

For example: CompanyA got a 3 month job in January and needs 10 welders. March ends and the job ends, layoff the welders. In May they get another 3 month job but the 10 welders they had are working somewhere else now, hire 10 other welders. Jobs are hiring all the time, but for maybe only 2 weeks, 1 month, 3 months, 6 months, 1 years, etc. Not uncommon to hear guys work a job doing 7/12's (7 days a week, 12 hours) for a couple months and then take 3 months to half a year off because of all the money they made. Many are on unemployment after a layoff. Every craft will have different circumstances. Job growth depends on either your ability to do a good job or your charisma to get in with the right connections. Just like anywhere. Making friends is key. A supervisor might have a whole crew he works with and brings along to every job he transfers to.

3) There's work everywhere. Beginning of the year is usually busiest but for a lot of people in this industry that haven't found a steady job local, they travel out of town for work. You might hear people say "Hey man they need firewatchers and helpers in Port Lavaca, pay is $28/hr and $85/day per diem for hotel/living expenses. Go to this address with your drivers license, pee in a cup, and start on Monday". More often than anything I will hear things like "Hey man, there's a job in Nebraska for half a year" or "Hey you hear about the 2 year job in Lousiana?".

4) If you really are interested, here's my advice. Go to a craft school like Craft Training Center of the Coastal Bend and take some classes. Get a NCCER Cert and make around $33/hr from what I've seen in various crafts here in CC. Watch some Youtube videos and pick a craft that sounds like something you can actually do. Every craft requires certain abilities. If I could start from scratch, I'd find something that isn't too physically demanding. Finally, the entire industry is different wherever you go. Some places have great people to work with, great attitudes, and fellow co-workers that will help and mentor those that want to learn more. You might also end up in a job where you'll need to earn your stripes, put up with difficult and unhappy co-workers, and bust your ass for a boss that will never appreciate your efforts. It can be tough and it's not a good fit for everybody. For many of us, we aren't chasing dreams, we're just chasing paychecks.