From the moment you or your child catches the 'skating bug' you'll have skates on the brain. I recommend completing at least one session of learn to skate first, once you register for the next one or if you want to begin private lessons, having your own skates is the next important step. Many rinks have decent quality rental skates, and I'd choose them over a lot of the skates that I see skaters step on the ice in. One issue with rentals is that you are not likely to get the same pair every time and also they are not designed to for skating moves beyond the very basics. Some rinks have pro shop on-site, stop in and talk to them. They will be more than happy to make a recommendation. If your rink does not have a pro-shop just call the nearest one and they'll be happy to answer questions. Of course your best source of information is a skating coach, they will either answer your question or get you pointed in the right direction.
ASK A COACH :)
You get what you pay for. If quality skates aren't in the budget, wait until they are. I can't tell you how many skaters buy a very inexpensive pair of skates only to be disappointed and forced to replace them after a few months. Go with a reputable brand. You can save money by going to the brands website and following their sizing information and then ordering yourself on a site like Amazon or eBay. Most experts will tell you not to size up. As a mother I understand how quickly little feet grow, and on the young ones (under 8 years) I think sizing up no more than half a size is usually ok. I personally often recommend Riedell or Jackson skates, they both offer several good options for entry level skates (and high levels too). For your first 2-3 pair of skates this a great way to do it. You can get skates with the blades included for around $100-$250. In most cases you will not find quality skates at a store unless it is a skating pro shop. So plan to have to order them. Do not buy skates form a big chain/box/sporting goods store.
ASK A COACH :)
Once a skater is ready to learn an axel and double jumps it's time to start buying your skates from a pro shop and getting professionally fitted. This is also about the right time to upgrade buying the boots and blades separately. Higher level boots and blades are always sold separately to allow you the right combination of equipment for your needs. Also, many skaters will wear out boots before they need new blades and the blades can be remounted to the new boots. Now you will be looking about $400 and up for skates.
ASK A COACH :)
Sharpening and accessories! If you order skates online that have blades already attached they may say that they will arrive sharpened, this is a factory sharpening and you will still want to get them sharpened before skating on them, trust me on this. All rinks have sharpening services. You will also need soft blade covers for when the skates are not in use. These are usually called soakers (because they soak up the moisture) and you will need hard plastic guards for walking to and from the ice. You do not want to walk around the rink (or any place) without guards on because you could damage your blades and cause injury to yourself. Never leave the hard guards on in the skate bag, this can cause your blades to rust. Avoid leaving skates in the car and if possible take them out of the bag to air out and dry once you are home.
Have questions? ASK A COACH :)