We have a hedge of these conifers. They are the tall slim trees -they are not leylandii that you have in UK, so they don't get out of hand. They have small pine cones appear from time to time. They are very cheap to buy - small ones approx. 1.5 euros each. You can buy them slightly bigger for 5 euros and larger still for 10+ euros, but they grow fairly quickly, so unless you want to cover something immediately, the small ones are easier to plant and cheaper! You need to plant them approximately 18 inches apart and mound the earth aroud the base. Make sure you give them a regular watering to get them started. We bought 60 to plant along our garden and they are growing well. When they reach the required height cut the main top stem and this allows the trees to thicken up and gives a lovely green backdrop.
Be careful when selecting your trees, some are bushier (like xmas tree shape) and are often mixed in with the other tall slim variety. Having said that, we have some of these mixed in with our hedge and they look great. Good time of year to plant them - gives them time to root and establish before the blistering heat in summer months.