Well, throw us a bone here. It’s like going “recommend me a bike, one like my old one, with a wheel at each end.”
What’s your usage? A laptop for occasional web use is going to be wildly different from a games platform or a graphic design system. You want one of a similar screen size to your old one; how big is that? Do you mean inches or resolution? We’re not psychic (and I’m damned if I’m googling to find out information you could’ve readily given us).
Did you like the old Dell? Happy as a brand? Or did you hate every minute of it?
If your only requirement is ‘cheap’ and a given size, I’d suggest going to Cash Converters, pretty much everything they have there will meet your needs.
Generic advice, go for an established brand name rather than a shop own-brand. Prioritise memory over CPU. Other than that, who knows until you tell us what you need.