i've been thinking about conectiing to adsl. i want to save money and install it myself.Is it difficult and what is involved?
is there much difference between 56k and 256k? will i notice the difference?

If your ISP allows you to install it yourself, you shouldn't have any problems. Its pretty simple, but some ISPs require you to buy the modem from them, and require that they send their monkey..er technician, to install it.
As for difference, oh yea, you'll see a huge difference. When I first went from 56k dialup to cable, it was 256k and it was a huge improvement. People with mbit and faster connections will tell you its still slow, but we aren't comparing it to a 1mbit, we are comparing it to a 56k(which is really a max of 53.3k according to FCC regulations)
dl speed with 56k= ~7KB/s
dl speed with 256k= ~32KB/s

Dont worry about installing it yourself, you are usually supplied instructions by the ISP.
This is usually done once your phone line is ADSL enabled by your local telco.

Performance wise from my experience, yes it will be faster. You can download bigger files faster and do things you wont be able to with a 56k.

the isp i intend to connect to allows me to self install even when i buy a modem from them. i just want to make sure theres no tricky configuration problems i might come across and have to call the technicians in.

As I have mentioned earlier, your ISP will be more likely to supply your step by step instructions to configure them since they allow their customers to install themselves.

what's the average speed of cable? i know it can go faster than adsl but does it stay at high speeds constantly? how slow can it get due to congestion?

I don't know about where you live, but in my city, the cable company offers 512K/256K only. ADSL is offered at 256K/128K, 768K/256K, and 1.5M/256K, which is what I have.

I've had cable, and it slows down as more local users get online. I have never experienced this with ADSL, it seems to stay the same, except when the whole net gets congested. I know it's a matter of preference, but I like DSL better.

DSL and cable connection speeds depend on the products offered by the ISP.

The (theoretical) maximum for consumer cable is 10Mbit and 8Mbit for DSL. Not many ISPs actually offer these speeds because such data rates can't usually be guaranteed.

Since cable users share the local loop you may experience slowdowns during peak hours if many people in your neighbourhood have cable internet and your cable company is cheap and/or lazy.

With the isps in australia, cable speeds are uncapped. It doesnt tell us how fast it can get. Adsl comes at 256k, 512k and 1.5m. all my friends prefer cable. i plan to get adsl but i'm wondering whether it'd be better to invest in cable rather than adsl 256k/64k even though cable is much more expensive to install.

I reckon its personal peference.

Personnally if I were in your shoes, I would go for ADSL.

With iiNet planning to offer uncapped broadband this mid july, you can expect other ISPs updating soon their plans towards "unlimited broadband".

Think of it this way....Cable is wide network where people connect through the same connection. In simpler terms, it slows down as more people get on because they're all sharing one connection. With DSL, it is a direct connection to your house/business. So as people get on, it doesnt get slower unless huge numbers are using the service as Olefarte mentioned.

I have 768k adsl, it dls from 70 to 100kb a second.

SUPER easy to setup

Highly reccomnend

ADSL vs Cable

I have a chart that tells you the pro's and con's of cable and ADSL if you care to take a look corey. http://www.dsl-experts.com/cable_modem_f_a_q_.htm this is for american dsl and cable services but it should still give you a good idea what to expect. I also have an ADSL vs dialup chart at http://www.dsl-experts.com/dsl_f_a_q_.htm . I'd say it depends on the costs of DSL or Cable in your area. often here in the states cable companies run specials where they do the install for free, check and see if you can find anything like that before you buy. Keep in mind you might have to sign a contract of atleast a year for either of these services so it's good to do as much research as possible before commiting to anything. Keep in mind that you also have security issues when you have an always on Internet connection. I hope this post helps in your broadband search :grinthumb

- Colin