I think I am totally lost when it comes to hacking.... how do you determine threshold on hacking tests?

And what programs and skills are really needed by a hacker?

i disagree !!

Most thresholds are up to the GM based on the table on p. 56 where average thresholds are from 1 to 4. Thus, for hard tasks, you have a higher threshold. Other thresholds are determined by the action you're taking. For example, hacking your way into a system is an extended test Hacking + Exploit (Firewall, 1 Initiative Pass) thus the threshold is based on the Firewall of that which is being hacked. If you can give us a specific test you don't understand we can probably help better.

As for programs and skills, that depends on what you want to do. Obviously Computer and Hacking are two important ones, and Electronic Warefare isn't anything to turn down if you have the points. Software and Hardware can be skipped unless your concept requires them our you're going to be breaking and entering (you need Hardware tests to defeat some physical security systems).

Programs, Exploit and Stealth are the big hacker tools, without those two you can't even get into systems without being detected. After that, Edit and Browse are probably both important to get around a system and do anything with it. Scan and Sniffer are nice to detect wireless nodes and intercept wireless transmission. After that, it's again, up to the character. If you're more fight than flight, then you'll want Attack, Black Hammer, and/or Blackout plus Armor. Gonna run when discovered? Probably you'll want Spoof to help out with the Redirect Trace action's you'll want to be performing. Basically, if you read through the hacking chapter and make a note of what actions you think you're most likely to perform, that's the programs you want.

If you want to be safe, get them all except Reality Filter and ECCM. Those two are definately supportive programs and can be done without. All of the other ones have specific applications for specific actions. 'Course, if you've got the cred, you might as well get these two as well.

Your mom.

There's no way to actually sign up for the newsletter according to the RAW. It's mentioned in fluff but there's no Avail codes or cost listed for it anywhere. Your GM may be comfortable making up stats for it, but I'm not.

The very existence of the newsletter is obviously unrealistic and destroys the street-level feel that the system is obviously geared towards.

The newsletter was invented by an author interpreting canon differently. It was later announced that it was an intentional move.